Efy Mar09

Salary Survey Results Tips for Buying of Electronics Industry Personal Music Players

ISSN 0013-516X

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www.efymag.com

South Asia’s Most Popular Electronics Magazine

march 2009 Vol. 41 No. 3

Stage All Set for

hdTV Make A Versatile Frequency Counter

Flexible Circuits Getting Better

Scatternets Rekindle Hope in Bluetooth

A Smart Charger for Li-ion Batteries

Vol. 41 No. 3

march 2009

41st Year of Publication

Since January 1969 www.efymag.com

Contents 28

Editor

: Ramesh Chopra

Editorial correspondence

: Editorial Secretary Phone: 011-26818096 E-mail: [email protected] (Technical queries: [email protected])

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Advertisements new delhi (Head Office)

: Harpal Bisht D-87/1, Okhla Industrial Area, Phase 1, New Delhi 110020 INDIA Phone: 011-26810602, 26810603 Fax: 26817563 E-mail: [email protected]

Mumbai

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Bangalore chennai Kolkata

: Jayashree No. 9, 17th Main, 1st Cross, HAL II Stage Indiranagar, Bangalore 560008 Ph: 080-25260394, 25260023; Fax: 25260394 E-mail: [email protected] : M. Nackeeran DBS House, 31-A, Cathedral Garden Road Near Palmgroove Hotel, Chennai 600034 Ph: 044-28275191; Mobile: 09962502404 E-mail: [email protected] : D.C. Mehra 61-A, Park Street, Kolkata 700016 Ph: 033-22294788; Telefax: 22650094 E-mail: [email protected] Mobile: 09432422932

Pune

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Hyderabad

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Gujarat:

: Shambhubhai Patel Ph: 079-22139841 E-mail: [email protected] Mobile: 098252 00451

singapore

: Ms Peggy Thay Publicitas Singapore Pte Ltd 72, Bendemeer Road, #02-20, The Luzerne, Singapore 339941 Phone: +65-6836 2272 Fax: +65-6297 7302 E-mail: [email protected], [email protected]

United States

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Printed, published and owned by Ramesh Chopra. Printed at Nutech Photolithographers, B-38, Okhla Industrial Area, Phase-I, New Delhi, on the first day of each month and published from D-87/1, Okhla Industrial Area, Phase I, New Delhi 110020. Copyright 2009. All rights reserved throughout the world. Reproduction of any material from this magazine in any manner without the written permission of the publisher is prohibited. Although every effort is made to ensure accuracy, no responsibility whatsoever is taken for any loss due to publishing errors. Articles that cannot be used are returned to the authors if accompanied by a self-addressed and sufficiently stamped envelope. But no responsibility is taken for any loss or delay in returning the material. EFY will not be responsible for any wrong claims made by an advertiser. Disputes, if any, will be settled in a New Delhi court only.

Stage All Set for High-definition TV

Career

Empower Yourself with Power Electronics

Rs 1,445 1,015 385

— — US$ 100

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For receiving Annual Directories (priced at Rs 300 with CD), please add Rs 250 for each year (including handling and forwarding). Kindly add Rs 50/- for outside Delhi cheques. Please send payments only in favour of EFY Enterprises Pvt Ltd Non-receipt of copies may be reported to [email protected] mentioning your subscription number

Qs&As.......................................................... 16 TECHNOLOGY NEWS..................................... 20 Circuit Ideas.............................................. 81 New Products......................................... 115 INDUSTRY NEWS......................................... 118

EFY Report

Salary Survey: Electronics Industry Maintaining a Vigil

Electronics Mart................................... 130

48

Manufacture

ADVERTISERS’ INDEX ................................. 145

52

Construction

60

Construction

87

Software Section

92

Power Supply

Biz Ads...................................................... 123 Bookshelf............................................... 142 Subject & ORGANISATION INDEX............... 144

Flexible Circuits Getting Better

Microcontroller-based Ring Tone Player

Charging Lithium-Ion Batteries

107

Do-IT-Yourself

112

Wireless

 • m a r c h 2 0 0 9 • e l e c t ro ni c s f o r yo u

73

Buyers’ Guide

 World’s

First 200Hz LCD TV  Gen-next Keyboards and Pianos  Multimedia Projectors  Affordable Mobile Phones  Portable Music System  Portable DLP Projectors  Tabletop Desktops  Ultra-Short-Throw Projector  Airtel IPTV Service

Personal Music Players

Reading the Datasheets of Electronic Devices—Part 1 of 3

A Versatile Frequency Counter

Bluetooth Scatternets: A Cost-Effective Solution for Communication

Interview

*For anniversary offer, refer to page no. 75

First Look!

LAN-based Online Exam

100

140

68

PC-based Wireless Stepper Motor Control

Design

Period Domestic Digital Overseas Year With CD Without CD (With CD) (Without CD) Rs 1,445 1,015 385

EFY-CD......................................................... 08

43

SU B SCRI PT IO N RATES*

Five Rs 2,160 Three 1,510 One 575

Departments LETTERS ..................................................... 12

36

ISSN-0013-516X

Technology Focus

“Thin-film modules reduce the cost of energy generation”— Dr Randhir Thakur, senior VP and gm of Applied’s SunFab Thin Film Solar and Display Business Group, and Rajiv Arya, CEO of Moser Baer Photovoltaic (MBPV)

Technology Focus: LED Lighting Buyers’ Guide: Which Watch? Survey/EFY Report: Embedded Systems w w w. e f y m ag . co m

EFY-CD Page

In this Month’s

Focus on Multimedia TOP 4 software MultiMedia Office

FreeMat

Scilab

Abiword 2.6.6

 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

Video DVD Maker.

Video DVD Maker is a flexible, easy-to-use and focused DVD maker. It allows you to get high-quality output, even if you don’t know the subtleties of recording technology. The intuitive interface leads you through a comprehensive set of logical steps to capture and output DVDs. Video DVD Maker enables you to capture video from various video devices, including TV tuners and Web cameras, as well as import video from any video file, including AVI, DivX, XVID, MPEG-4, MPG, WMV, ASF and MOV. You can easily play these videos on your home DVD player after burning to a CD/DVD. Avidemux. Avidemux is a free video editor designed for simple cutting, filtering and encoding tasks. It supports many file types, including AVI, DVD-compatible MPEG files, MP4 and ASF, using a variety of codecs. Tasks can be automated using projects, job queue and powerful scripting capabilities. Avidemux is available for Linux, BSD, Mac OS X and Microsoft Windows. MultiMedia Office. MultiMedia Office is ideal for business, home or educational use. Create or edit documents, spreadsheets, drawings, presentations, photos, databases, web-

pages, audio and video. And combine these different elements into a single file that meets the ISO standard open document format. FreeMat. FreeMat is a free environment for rapid engineering, scientific prototyping and data processing. It is similar to commercial systems such as MATLAB from MathWorks and IDL from Research Systems. It is open-source and runs on Windows, Linux and Mac OS X. Scilab. This open-source software provides a powerful computing environment for engineering and scientific applications. It includes hundreds of mathematical functions with the possibility to add interactively programs from various languages (C, C++, Fortran, etc). It has sophisticated data structures (including lists, polynomials, rational functions and linear systems), an interpreter and a highlevel programming language. Abiword 2.6.6. AbiWord is a free wordprocessing program similar to Microsoft Word. It currently runs on Linux, Mac OS X and Microsoft Windows. It has a comprehensive language database with multiple languages, support for tables and footnotes, as well as a spell checker and an advanced grammar checking system. w w w. e f y m ag . co m

Letters Invitation Border Security Force Communication and IT Directorate, CGO Complex, New Delhi, is a subscriber to EFY magazine. The articles published in EFY are very educative and these are passed on to technical staff in the ranks of DIGs, commandants and deputy commandants. On behalf of the directorate, we invite writers of such topics as new telecom services on the way, WiFi and WiMAX, 3G audio management and telemedicine to deliver lectures at our headquarter. B.S. Kushwah, DIG Through e-mail

EFY-CD Content Many thanks for providing Ubuntu operating system in the EFY-CD of January issue. It’s a very good operating system. Please publish some software and circuit diagrams for programming the Atmel microcontroller under Ubuntu operating system. Subrat Kumar Mallik Through e-mail  Please include: 1. Free software like OCR in the EFY-CD. 2. Buyers’ guide on car stereos in the magazine. Jiji Abraham Kochi

Test for Technocrats I suggest EFY to conduct a technical test for the technocrats nationally. This will help those who are doing research work in various fields of electronics. Anshul C. Kansara Navsari

Software Codes The software codes of technical articles published in EFY magazine are provided only in the accompanying CD. I request EFY to provide all the codes online. I have subscribed to EFY magazine online, but could not find the subscription number after login to this site. Please tell me where can I find it. Gerard Canekeratne Oman EFY: Thanks for pointing out an area for improvement. We have taken up this project, and it will be implemented 1 2 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

very soon. Subscription numbers are currently not available on the website.

Designing Low-Power Products Thanks for publishing the article series ‘Designing Low-power Products Using MSP430 Microcontrollers’ in January and February issues. I request you to publish a similar kind of article series on Cypress CY3270 and Texas Instruments’ MSP430RF2500 microcontrollers. I also suggest you to provide a reference booklet on MSP430F2013, CY3270, Atmega16 and MSP430RF2500 instruction sets and pin configurations with EFY magazine every quarter. It would be useful to hobbyists, students and professionals in working on projects or preparing for interviews. Maneesh Sharma Navi Mumbai

Circuit Ideas of Anniversary Issue I have been a regular reader of EFY for many years. In January issue, I have noticed that: 1. In ‘Running LED Lights’ circuit, a 12V transformer has been used. I feel a 7.5V or 9V transformer will be a better choice for logical and economical reasons. 2. In ‘Top 10 Circuits,’ two emergency light circuits and two 3-phase application circuits have been included, which are electrical in nature. You should publish a variety of circuits for different readers. Rakesh P. Through e-mail EFY: Thanks for your feedback and interest in EFY magazine. As regards your observations: 1. Use of a 12V transformer in the ‘Running LED Light’ circuit is alright in a hobbyist circuit design. Optimisation can always be done by the users for whatever reason they may think appropriate. 2. The two emergency light circuits are quite different and these were chosen based on the readers’ feedback on EFY website. The automatic phase changer is designed for balancing the loads on different phases and also for

DTH TV The article titled ‘Which DTH TV for You?’ published in February issue, was authored by Amit Goel, with some inputs from Uma Bansal. We are sorry, Mr Goel’s name was inadvertently left out as author of the article. Mr Goel has several years’ experience in the field and runs his own blog, which can be seen at “http://amitslab. com/blog”

providing supply to essential loads in the event of failure of a particular phase, whereas the three-phase appliance protector provides supply to the appliance only when all the three phase are available. Notwithstanding the foregoing, selection of these two circuits was also based on the readers’ feedback.

Heart Rate Meter Regarding the ‘Microcontroller-based Heart Rate Meter’ project published in May 2008 issue, I have the following queries: 1. In the software program, it is mentioned that time is noted down after the end of three crossings. Are these three crossings related to P, R, T waves? In practice, while measuring ECG, the ECG waveform also consists of time period after ‘T’ wave of the first ECG and before ‘P’ wave of the second ECG waveform. Thus the time should be read before ‘P’ wave of the next ECG. 2. The time taken from time-count register is converted in terms of the number of 4ms intervals. I don’t understand why 4ms interval is taken? 3. How can I stop the ambient light from interfering with the readings? Ms Amruta Pise Mumbai The author Prof. K Padmanabhan replies: 1. Do not confuse ECG with the blood flow signal into the finger. It is just the blood flow signal that is used for counting here. Refer to the waveform shown in the article. 2. You can use any unit for measuring time, provided you know the basic unit; just as you can measure weight in grams or kilograms, depending on the measured value. w w w. e f y m ag . co m

Letters Here 4 ms is well-nigh sufficient. If we measure in 1ms units, we’ll get a larger number for the time unit between two (blood) pulses, and we will then be using a larger divisor to find the rate of blood flow per minute. 3. The problem of ambient light has been explained in the text. Please read the article thoroughly and your doubts will be cleared.

Speedometer-cumOdometer I have constructed the ‘Microcontroller-based Speedometer-cum-Odometer’ project published in Nov. 2008 issue, as per the instructions given in the text. I have downloaded the ‘hex’ file but nothing was displayed on the LCD screen. Also, the Assembly program is not clear. Please help. Anil Patil Ulhasnagar  Regarding this project, I have the following doubts: 1. How to make the LCD module illuminate? 2. What is the name of the box that encloses the LCD module and the circuit board, and how to fix it in the handle-bar? 3. Do I need to provide water-resistive coating for the reed switch? 4. What changes are to be made in the program and the circuit, so that it can be used in my Honda Unicorn bike? Roshan George V. Cochin The author Arun Kumar Vadla replies to Anil Patil: If you are testing the project on a simulator software, nothing will display on the LCD. You have to test the project in real hardware after programming the microcontroller, first with ‘init eeprom.hex’ program and then with ‘speedo.hex’ program. The Assembly code is well commented. You’ll find explanation of each line of the code. I have been using this speedometer since one-and-a-half years and it is working well without any problem. Reply to George Roshan: 1. Backlight connections are usually made at pins 15 and 16 of the LCD module. The anode (pin 15) should be connected to +5V DC through a series 1 4 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

resistor. Connect the cathode (pin 16) to GND. 2. There is no particular name for the enclosure, but I have used the enclosure of an electronic choke and made a slot according to LCD dimensions. 3. Since reed switch is encapsulated in glass, it does not require any special coating. 4. In the article, I have given the formula for modifying the program for any wheel dimensions. First, calculate the radius of the wheel and then use the formula given in the text to get the constant. I have illustrated these steps in the article, so please read carefully.

Mobile Bug Regarding the ‘Mobile Bug’ project published in January 2008 issue, I have the following queries: 1. It is mentioned in the article that the circuit can sense the presence of an activated mobile phone. Does it mean a switched-on mobile phone without call/SMS/data transmission? 2. Can we use an FM radio’s telescopic antenna in place of the 12.7cm (5-inch) antenna shown in the circuit diagram? Prakash New Delhi The author D. Mohan Kumar replies: 1. The mentioned circuit senses an activated mobile phone. That is, switch on the circuit and it will detect the signals in response to a call, SMS or video recording in the mobile phone. 2. A small telescopic antenna can be used. The antenna is not necessary if the 0.22µF capacitor is protruding from the case.

Staircase Light In the ‘Staircase Light With Auto Switch Off’ circuit published in January issue, the schematic diagram is wrong. Pin 2 of IC 555 appears at two locations. Ramasamy Mysore EFY: Thanks for pointing out the printing error in the circuit diagram. In the circuit tested, pins 6 and 7 of 555 timer are shorted at the junction of resistor R7 and capacitor C4. Kindly read wrongly-printed pin 2 as pin 7. w w w. e f y m ag . co m

Qs&As is the difference beQ1. What tween condensers and capacitors?

Sunil Prasad Through e-mail From electrical engineering point of view, condensers and capacitors are the same. However, you may often come across condensers also being referred to as devices used to condense vapour into liquid, a range of laboratory glassware used to remove heat from fluids, heat exchangers installed in steam-electric power stations to condense turbine exhaust steam into water, air coils used in HVAC refrigeration systems, a group of lenses mounted below the stage of an optical microscope to concentrate light, and condenser microphones that convert sound waves into an electrical signal. An ideal capacitor is characterised by a single constant value called ‘capacitance.’ This is defined as the ratio of the amount of charge in each conductor to the potential difference between them. The unit of capacitance is thus coulombs per volt, or farads. Higher capacitance indicates that more charge can be stored at a given voltage. In practice, the insulator allows a small amount of current through, called leakage current. The conductors add a series resistance (specifically called equivalent series resistance), and the insulator has an electric field strength limit resulting in a breakdown voltage. The properties of capacitors in a circuit may determine the resonant frequency and quality factor of a resonant circuit, power dissipation and operating frequency in a digital logic circuit, energy capacity in a high-power system, and many other important aspects.

A1.

is the working principle Q2. What behind touchscreen mobiles? How do they differ from ordinary mobiles? What are their drawbacks? Anuja Wadatkar Through e-mail Mobile phones may use two types of input devices. In reg-

A2.

1 6 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

ular mobile phones, a keypad type of device is used, which is mounted separately from the screen of the cellphone. Whereas in touchscreen cellphones, a touch screen is a cellphone display screen that also acts as an input device. The touchscreens are sensitive to pressure; a user interacts with the mobile applications by touching pictures or words on the screen. Most mobile phone keyboards are basic in that they use a tactile surface you are accustomed to touching, and underneath is a basic rubber peg (black dot) which travels some depth until it encounters resistance in the form of the actual keyboard surface which is sometimes called a ‘bubble board.’ This is basically a semi-circle of aluminium shaped in the form of a dome and provides that springing effect of key and feedback on your finger when you press down and the button regains its at-rest shape and normal position. Touchscreen technologies used in mobile phones include resistive, capacitive and surface-wave based system. Resistive. The resistive system consists of a normal glass panel that is covered with conductive and resistive metallic layers. These two layers are held apart by spacers, and a scratchresistant layer is placed on top of the whole setup. An electrical current runs through the two layers while the monitor is operational. When a user touches the screen, the two layers make contact exactly at that spot. The change in the electrical field is noted and the coordinates of the point of contact are calculated by the processor. Once the coordinates are known, a special driver translates the touch into something that the operating system can understand, much as a computer mouse driver translates the movements of a mouse into a click or a drag. The change in the electrical current is registered as a touch event and sent to the controller for processing. Resistive touchscreen panels are generally more affordable but offer only 75 per cent clarity and the layer

can be damaged by sharp objects. Resistive touchscreen panels are not affected by outside elements such as dust or water. Capacitive. In the capacitive system, a layer of an electroconductive material (most often indium tin-oxide) that stores electrical charge is placed on the glass panel of the monitor. When a user touches the monitor with his finger, some of the charge is transferred to the user, so the charge on the capacitive layer decreases. This decrease is measured in circuits located at each corner of the monitor. The computer calculates, from the relative differences in charge at each corner, exactly where the touch event took place and then relays that information to the touchscreen driver software. One advantage of the capacitive system over the resistive system is that it transmits almost 92 per cent of the light emitted from the monitor, whereas the resistive system transmits only about 75 per cent. This gives the capacitive system a much clearer picture than the resistive system. Also, the capacitive system has a very long life (about 225 million clicks). The bad news is that this touchscreen type cannot be activated by contact with inanimate objects (e.g., the gloves that you might be wearing). There are mainly two subtypes: one cannot register more than one touch at a time, while the other, called ‘MultiTouch’ (used in Apple iPhone and iPod) does. Surface wave. Surface-wave technology uses ultrasonic waves that pass over the touchscreen panel. On the monitor of a surface acoustic wave system, two transducers (one sending and the other receiving) are placed along the ‘x’ and ‘y’ axes of the monitor’s glass plate. Also placed on the glass are reflectors—these reflect an electrical signal sent from one transducer to the other. The receiving transducer is able to tell whether the wave has been disturbed by a touch event at any instant, and can locate it accordingly. When the panel is touched, a portion of the wave is w w w. e f y m ag . co m

Qs&As +12V

C1 1µ 16V

XTAL

IC1 AT89 C2051

5 C2 33p 10

19

1

10

18

18

2

17

17

3

16

16

4

IC2 ULN 2803

LED2

20

15

15

5

14

6

13

7

12

12

8

11

14

RL1-RL5 = 12V, 1C/O RELAY LED1-LED5 = 5mm RED LED

RL3 N/O

R4

N/C RL4 N/O

R5

R2-R6 = 2.2K XTAL = 11.052MHz

N/O N/C

13

9

RL2

R3

LED3

C1 33p 4

BLUETOOTH MODULE

N/O N/C

LED4

1 2 R1 56K

RL1

R2

N/C

LED5

CELLULAR PHONE COMMUNICATION ADAPTER

RNW-10K x 8

CTS-1 VCC GND TX-0 RX-1 RTS-0

BLUETOOTH

CELLULAR PHONE

INTERNET

LED1

+5V

R6

RL5 N/O N/C

DEVICE 1 230V AC 50Hz

DEVICE 2 230V AC 50Hz

DEVICE 3 230V AC 50Hz

DEVICE 4 230V AC 50Hz

DEVICE 5 230V AC 50Hz

Circuit for home appliance control via Bluetooth-enabled cellular phone

absorbed. This change in the ultrasonic waves registers the position of the touch event and sends this information to the controller for processing. The wave setup has no metallic layers on the screen, allowing for 100 per cent light throughput and perfect image clarity. This makes the surface acoustic wave system best for displaying detailed graphics (both the other systems have significant degradation in clarity). Surface-wave touchscreen panels are the most advanced of the three types, but these can be damaged by outside elements. Another area in which the systems differ is the way stimuli is registered as a touch event. A resistive system registers a touch as long as the two layers make contact, which means that it doesn’t matter if you touch it with your finger or a rubber ball. A capacitive system, on the other hand, must have a conductive input, usually your finger, in order to register a touch. The surface acoustic wave system works much like the resistive system, allowing a touch with almost any object—except hard and small objects like a pen tip. can we interface a blueQ3. How tooth module with a microcontroller to control devices like door1 8 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

locks and lights from a cellphone? Premrashan Nair Bangaluru The circuit of a simple cellphone-based device-control system using bluetooth communication link and microcontroller is shown above. It can be easily designed by engineering students and hobbyists. The advantage of bluetooth technology is that it doesn’t require line-of-sight for signal transmission from the transmitter to the receiver. This device control system overcomes the problems of manual switching (on/off) of different devices through bluetooth-enabled cellphone communicating with the bluetooth module interfaced with the microcontroller. It is a simple and cost-effective design to solve the problem of remote control for whatever reason it may be. The circuit consists of a cellphone attached to a bluetooth adaptor (one could use a cellphone having inbuilt bluetooth), a bluetooth module interfaced with microcontroller AT89C2051, a driver IC ULN2803, five 12V relays, LEDs and associated discrete components. At the heart of the circuit is microcontroller IC AT89C2051 (IC1). It is

A3.

a 20-pin, 8-bit microcontroller with 2 kB of Flash programmable and erasable read-only memory (PEROM), 128 bytes of RAM, 15 input/output lines, two 16-bit timers/counters, a five-vector two-level interrupt architecture, a duplex serial port, a precision analogue comparator, on-chip oscillator and clock circuitry. The ULN2803 (IC2) consists of eight npn Darlington-connected transistors, which are ideally suitable for interfacing between low-logic-level digital circuitry and the higher current/voltage requirement circuits such as lamps, fans or other similar loads for a broad range of computer, industrial and consumer applications. It is used here for driving the devices through relay contacts. You can write a simple software program for the microcontroller of the bluetooth-enabled cellphone, employing simple coding and decoding of remote signals to perform switching of devices. Answers compiled by Air Cmde (Retd) P.D. Badoni Letters and questions for publication may be addressed to Editor, Electronics For You, D-87/1, Okhla Industrial Area, Phase 1, New Delhi 110020 (E-mail: [email protected]) and should include name and address of the sender. w w w. e f y m ag . co m

Fact-filled AND the most happening current affairs from around the world

Technology News ‘Evolving’ robots

Taking cue from biological evolution, the scientists have developed a robot with a software ‘brain’ that automatically grows in size and complexity as its physical body develops. The only but major difference is that it does this trick in hours. Existing robots cannot usually cope with physical changes—the addition of a sensor or new type of limb, say—without a complete redesign of their control software, which can be time-consuming and expensive. So artificial intelligence engineer Christopher MacLeod and his colleagues at the Robert Gordon University in Aberdeen, UK, created a robot that adapts to such changes by mimicking biological evolution. “If we want to make really complex humanoid robots with ever more sensors and more complex behaviours, it is critical that they are able to grow in complexity over time—just like biological creatures did,” he says. The brain of Macleod’s robot assigns new clusters of ‘neurons’ to adapt to new additions to its body. The robot is controlled by a neural network—software that mimics the brain’s learning process. This comprises a set of interconnected processing nodes which can be trained to produce desired actions. Such actions are shaped by adjusting the importance, or weighting, of the input signals to each node. Certain combinations of these sensor inputs cause the node to fire a signal—to drive a motor, for example. If this action works, the combination is kept. If it fails, and the robot falls over, the robot will make adjustments and try something different next time.

Flexible electronic books Screen breakage is a common complaint about today’s electronic books. However, UK-based Plastic Logic 2 0 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

World’s first flexible electronic book from Plastic Logic

claims to have developed the world’s first flexible electronic book with a bendy screen that can withstand a lot of tumble. Currently, the two most popular ebooks on the market, the Sony Reader and Amazon Kindle, are paperback book-sized devices that use B&W electronic ink displays. These consist of a plastic sheet containing pixel-sized voids, each filled with B&W ink particles. Electric fields attract the ink to the top of these voids to display print. The problem is, the transistors that apply these electric fields sit on a layer of glass, making the displays fragile. Plastic Logic has perfected a way of printing polymer transistors onto a layer of bendy plastic, allowing the screens to flex and bounce. This device will have wireless Internet connection and a touch screen, allowing use of a virtual keyboard for annotating text.

prerequisite for automated cars. The new devices are known as optical clocks because lasers measure the frequency with which electrons in atoms vibrate. This enables them to divide time into even tinier increments. The most advanced clock, created by researchers at the National Institute of Standards and Technology (NIST) in Boulder, Colorado, measures the vibrations of electrons in mercury ions and can go 1.7 billion years without missing a beat. A normal wristwatch, by contrast, loses about a second every week. The most exciting developments are likely to come in the field of global positioning systems (GPS), which track planes, ships and cars. GPS devices receive microwave signals sent by satellites and, by measuring the time these take to arrive, can pinpoint the location of an object on Earth to within 10 metres.

Optical clocks are the future

Universal charger for mobile phones

A new generation of clocks, called optical clocks, can keep time without missing a beat in almost two billion years. These clocks are so precise that they will allow satellites to track moving objects to within less than a metre—a

We all need to buy a charger with every new mobile phone. What if you can charge your phone from any available charger? This would not only make life easier for mobile phone w w w. e f y m ag . co m

consumers, but would be good for the environment too. The GSMA and 17 leading mobile operators and manufacturers said at the Mobile World Congress that they are committed to implementing a cross-industry standard for a universal charger for new mobile phones. The aim of the initiative, led by the GSMA, is to ensure that the mobile industry adopts a common format for mobile phone charger connections and energy-efficient chargers resulting in an estimated 50 per cent reduction in standby energy consumption; old chargers currently generate more than 51,000 tonnes of waste a year. The group plans to make a universal charging solution widely available by year 2012. It will use Micro-USB as the common universal charging interface. So by January 2012, the majority of all new mobile phone models available will support a universal charging connector and the majority of chargers shipped will meet the high-efficiency targets set out by the OMTP (Open Mobile Terminal Platform)—the industry body who developed the technical requirements for universal charging solution.

The free My Phone service will enable you to access, manage and back up your personal information on your device to a password-protected Webbased service. With automatic syncing and backup, you can count on your contacts, appointments, text messages and other information being kept up to date and easily restored should you lose or upgrade your phone. You will also be able to automatically upload photos and video from your Windows phone directly to the My Phone service. The new Windows phones are expected to be available in the second half of 2009.

Solar-powered touch phone Samsung Electronics has unveiled a solar-powered, full-touch-screen phone called ‘Blue Earth.’ By charging with the solar panel located on the back of the phone, users can generate enough power to call anytime anywhere. Blue Earth is made from recycled plastic called PCM, which is extracted from water bottles, helping to reduce fuel consumption and carbon emissions in

Next-gen Windows phones Microsoft is working with partners across the industry to deliver a new generation of Windows phones. These phones will be based on Windows Mobile 6.5 and feature a new user interface and a richer browsing experience. In addition, they will feature two new services: My Phone, to sync text messages, photos, video, contacts and more to the Web; and Windows Marketplace for Mobile, a new marketplace that will provide direct-tophone mobile applications and can be accessed from both the phone and the Web. The Windows Mobile 6.5 home screen will keep you up-to-date on important information by providing a dashboard-like experience to items such as new e-mails, texts, missed calls and calendar appointments. The improved touch-screen interface makes it easy to take action with a finger. 2 2 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

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the manufacturing process. The device, including charger, is free from harmful substances such as brominated flame retardants, beryllium and phthalate. Simple to set the screen brightness, backlight duration and Bluetooth to an energy-efficient mode, the unique user interface allows the user to be energy-efficient with just one click of ‘Eco’ mode. Through the ‘eco walk’ function the user can count his steps with an in-built pedometer, calculating how much CO2 emissions have been reduced by walking as opposed to motor transport. This unique function allows the user to calculate the value of this footprint through the number of trees that have been saved. The phone comes with a five-star energy-efficient charger which uses standby power of less than 0.03W.

Power meter from Google Google is developing a tool called PowerMeter that will show people their electricity consumption in near real time on a secure iGoogle gadget. The Internet giant is partnering with a host of electric utilities, device makers, regulators and other technology companies to deliver the data to consumers. The Google PowerMeter is a piece of software that people can view online to see how much electricity they are using every time they leave an appliance ‘on’ overnight. “If 5.3 million people used the new tool and cut back their electricity consumption by 10 per cent, they would save the equivalent of a gigawatt of power—enough to power a large city,” said Kirsten Olsen Cahill. The electricity-monitoring project is also consistent with Google’s goal of organising all the world’s information, Cahill said. Getting it to work, of course, will require aligning the interests of government, utilities and manufacturers of things like sensors for electricity meters.

World’s smallest TV data card ZTE claims to have developed the world’s smallest TV data card and also the world’s first plug-and-play data 2 4 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

CSR’s 802.11n range of devices add Wi-Fi to mobile devices

card. This USB modem (MF645) will enable you to watch digital television on a computer or laptop over a 3G connection. As the MF645 supports a download rate of up to 7.2Mbps, it offers a user experience that is similar to traditional TV sets.

World’s smallest 802.11n devices Cambridge Silicon Radio (CSR) claims to have launched the world’s smallest and lowest-cost range of 802.11n compatible devices to add to its Connectivity Centre line-up. At less than 16 mm2 of silicon, the UniFi UF6000 range of Wi-Fi chips are designed as embedded Wi-Fi products, making them a lowcost way of adding an 802.11n-enabled Wi-Fi to mobile devices. As more smart and feature-phones start to include Wi-Fi, the UniFi UF6000 Wi-Fi range provides manufacturers with a low-cost route to integrate Wi-Fi into handsets without compromising on performance or PCB space. By combining the UF6000 with the company’s recently launched lowcost GPS and Bluetooth chip, BC7830, CSR claims to offer customers Wi-Fi, Bluetooth, GPS and FM transmit and receive at a combined silicon area of 27 mm2—in comparison to competing solutions that are 40 per cent bigger.

The UniFi UF6000 range is fully compliant with IEEE802.11e QoS, WiFi Alliance WMM Power Save and 802.11n power saving, ensuring the lowest possible power consumption.

3D graphics in HDTV devices The graphical user interfaces offered by today’s set-top boxes (STBs) and digital TVs are primarily static and two-dimensional, and generally do not provide the level of performance demanded by the new Web-based interactive services. These services require a new breed of STB and TV user interfaces, based on advanced graphics technologies. STMicroelectronics offers broadcasters, operators and STB and digital TV manufacturers advanced 3D graphics effects within its latest high-definition video consumer platforms. Based on its latest generation of HD STB processors, including the STi7105, STi7111 and the recently announced STi7141, together with advanced software libraries, these digital consumer TV platforms offer advanced 3D graphic acceleration capabilities for a new generation of user interfaces, enabling 3D dynamic effects, such as transparency, mirroring, rotation and zoom-in and zoom-out; graphical compositions, or animations, combined with live HD w w w. e f y m ag . co m

video pictures; and HD-resolution dynamic 3D-looking user interfaces.

Share your whereabouts with friends Google has launched a new service, Latitude, that lets cellphone users share their location with friends. The service is part of Google Maps for Mobile—the company’s mapping software for mobile phones—but can also be used through a gadget loaded onto its iGoogle customised home page. It will work in 27 countries.

Google Latitude

Latitude can be downloaded on the mobile phone and invitations can be sent to friends and family to join the service. The location-based service only works with prior permission from the other person. Privacy settings can be adjusted in Latitude so that you share as much or as little about your location as you want, with whom you want. So for each person, you can choose to share your available location or your location when you travel to a different city, or you can be completely unavailable. Everything is under your control and, of course, you can sign out of Latitude at any time. The service also allows the user to communicate with friends through text messaging, instant messaging or a phone call. The application is independent of mobile operators and can be downloaded free from the Google website.

Futuristic transport system The implementation of an intelligent transport system (ITS) in India may now be postponed for some time. ITS refers to the use of new technologies like mobile phones and the worldwide web to guide traffic within a city. Once the system is in place, you can get mobile alerts while driving, indicating the routes with high traffic congestion and suggesting alternative route. It also means toll collection can be made electronically, which can enable you to drive through toll gates without facing a traffic snarl. In the case of an accident, an in-vehicle emergency e-call can be generated to the nearest emergency w w w. e f y m ag . co m

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point. The system can also provide information about parking space at any location in the city. The system is futuristic, but the fear is that terrorists can access information each moment on traffic trends in a city. They can know where the traffic is most congested so as to cause maximum damage. Officials also fear that the central control room—from where the entire ITS facility of a city will be coordinated—can become the target of a terror attack, exposing the city to great risks.

Emergency alert via mobile

with access to branded news content powered by Pressmart. By selecting the WAP link ‘Daily News’ on your Motorola phone, you can receive free news content and access your favourite newspapers while on the go. Newspapers offered on the service include Indian Express, The Financial Express, The Asian Age and Deccan Chronicle. A GPRS connection is required to access the free news content.

New Internet technology Atoall.com has launched a new Internet technology that uses keyboard shortcuts to access Google, Orkut, Yahoo!, Microsoft and similar such popular sites. For example, if you want to visit Google, you will have to type the following three consecutive letters in the keyboard, ‘gghhjj.com.’ To visit Orkut, you will have to just type ‘ookkmm.com.’ The technology makes it easier for

In an emergency you can register a missed call on Softspin’s server. The server, in turn, will send text messages to the pre-saved numbers anywhere in the world with details like the location of the call, the mobile service provider and the country. This way, the service alerts your friends and family that you need help. Softspin’s server number needs to be saved under a speed dial on a mobile or a landline to enable a quick call. “A message also reaches the caller saying that help is on its way. Even if the network is jammed, messages do pass through as they don’t require much bandwidth,” Atoall.com’s search engine Vinay Sathe, manthe illiterate to use the Internet as in oraging director of Softspin, says. der to access a Website, one has to type The service, Saviour, is available for three letters twice on the computer a lifetime registration fee of Rs 200 and Rs 120 as yearly subscription. keyboard which are in a straight line; e.g., ‘C’ or inverted ‘C,’ ‘V’ or inverted ‘V,’ twice, followed by dot (.) com or Motorola India and Pressmart Media, ctrl+enter (for www. .com). Shortcut a digital publisher, have announced keys are located together on the keya live news-on-the-mobile service on board, e.g., rrddcc.com, ccddrr.com, MOTO VE66, MOTOSURF A3000 and mmjjnn.com and nnjjmm.com. MOTOROKR EM35 phones slated for This technology search engine indistribution in India. vention also allows users to access their The service will provide you favourite games sites, videos, etc.

Live news on the mobile

Check efytimes.com for more news, daily 2 6 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

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Stage All Set for

high-definition TV Currently, HDTV broadcast does not take place in India, but the scene is hotting up with broadcasters producing content for HDTV and consumer electronics companies offering HD TV sets and set-top boxes uma bansal

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he highest form of digital television is all set to storm India. The greatest push has come from the government’s announcement that DD (Doordarshan) will broadcast the Commonwealth Games in high-definition (HD) format. HDTV programming through cable/satellite also is coming to India very soon, as the film industry has geared into HD production. For the end users, HDTV sets are already available in the market. Direct-to-home (DTH) TV operators

are trying to switch consumers at a premium for HDTV set-top boxes as INX Media and STAR TV are already producing content on HDTV. This is expected to take off by mid 2009. With so much of activity happening in this space, it is good time to dwell on the subject.

What is HDTV? There are two modes of TV transmission: analogue and digital. Digital TV comes in standard, enhanced and high-definition formats. Standard has a resolution of 480i, enhanced is 480p, and high-definition is 720p, 1080i and 1080p. Therefore HDTV has the high-

est-level resolution offered within the digital TV category. We can also infer that HD is digital, but not all digital TV is HD. HDTV has a 16:9 aspect ratio, which is the same as that of a movie theatre screen. HD resolution is listed in two different forms: “number of lines + type of scan” or “number of pixels” (vertical by horizontal). Tarun Jain, country head-India, Hitachi Home Electronics, gives a breakdown of the HD formats listed by how manufacturers label them on their product summaries: • 720p or 720×1280 - 720 lines, progressive scanned

HDTV LCD range by Samsung

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Bravia W-series HDTV by Sony

• 1080i or 1080×1920 - 1080 lines, interlaced scanned • 1080p or 1080×1920 - 1080 lines, progressive scanned The number of lines/pixels and type of scan matter because more lines/pixels and faster scan equal a better picture. In ranking the HD signal formats, 720p and 1080i are virtually equal in overall resolution, while 1080p is the best. HDTV also provides a cinematic theatre experience with Dolby Digital surround sound.

How does it differ from conventional TV? Jain explains that high-definition programmes are encoded with a type of resolution: 720p, 1080i or 1080p. The number stands for the amount of lines embedded within the signal. The letter describes the type of scan the television uses to display the picture. The ‘i’ means interlaced and the ‘p’ means progressive. The number of lines on a television is important because it allows for greater detail in the image. This is a

Analogue vs Digital TV In the basic analogue TV, the signals are transmitted as continuously varying radio waves. In fact, the video is transmitted in AM mode, while the audio is transmitted in FM. Like radio, analogue TV is subject to noise, interference (such as ghosting and snow) and attenuation with distance. In addition, the analogue TV signals require a wide bandwidth for their video and audio signals, which restricts the resolution and overall quality of the image. On the other hand, digital TV is transmitted as a series of binary numbers 0’s and 1’s (data bits of information). Computer processing is used to compress it, so it can be transmitted in a fraction of the bandwidth taken by the equivalent analogue TV signal. The freed-up extra space can be used for additional video, audio and text signals. As the signal is basically ‘on’ or ‘off,’ the viewer either sees an image or nothing at all. There is no signal loss due to attenuation as distance from the transmitter increases. In case the viewer is too far from the transmitter, there is nothing to see.

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HDTV by Hitachi

essentially nearly doubles the quality of picture. R. Zutshi, deputy managing director of Samsung India, says that highdefinition TVs offer the best TV viewing possible. HD format contains more and finer detail than other formats, so images can have almost lifelike clarity. The picture quality can be stunning, especially on a large, wide-screen set. In technical terms, HD images have higher definition, meaning more picture elements (lines or pixels) make up each image. HDTV provides wide-screen picture quality with compact disk (CD) sound quality. It has over twice the sharpness and clarity of analogue TV broadcasts together with a far superior colour resolution. With HDTV, problems such as double images from ghosting or multi-path, snow caused from a weak signal and picture sparkles from impulse noise are a thing of the past. These problems often seen on a conventional television broadcast just do not occur on high-definition TV. Also, the sound for conventional TV is only stereo. However, currently, HDTV broadcast does not take place in India, and the usage of HD resolution is limited to DVDs or other media only, so a high-

definition TV is effective if it is used for viewing DVD titles, etc.

What all is required for HDTV reception? You may ask “Do I need a special TV to be able to see HDTV?” The answer is that only high-definition televisions can display HD content in the HD resolution. Enhanced-definition televisions can display HD content in a 480p resolution, which is DVD quality. All other televisions that are analogue of standard digital will not be able to display HD content in an HD resolution because they lack the technology to do so. As is clear, anyone who owns a high-definition television can get high-definition content. One has three options: over-the-air signals, cable or satellite. Over-the-air high-definition signals are those that a typical rooftop antenna would receive. The signals are digital and encoded in HD. Over-theair signals are free to receive. The only cost out of pocket would be for the equipment needed to receive them. To receive HD programming from a cable or satellite provider, you would need to subscribe to their HD package if they have any. This subscription may not be free. The provider might require

Sources of HDTV Signals

similar concept to digital photos and how dpi determines print quality. In the conventional TV system, waves are scanned at 480i. This means that at a given point of time four hundred and eighty (480) lines of pictures are sent by the broadcaster to the television. The lines alternate between odd and even in a succession that is too fast for the human eye. HDTV sends around a thousand eighty (1080) or seven hundred and twenty (720) lines, which is more than double the conventional TV. By almost doubling the amount of lines in combination with the type of scan, HD 3 2 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

You can receive HD signals from the following sources: 1. Over the air with an antenna. Over-the-air signals are free to receive. However, to receive these signals, you need an HD tuner. Latest HDTVs have an HD tuner built into them. For HDTV televisions without a built-in HD tuner, a separate set-top HD tuner box can be rented from a cable or satellite company, or purchased. 2. Cable or satellite service. To receive HD programming from a cable or satellite provider, you would need to subscribe to their HD package if they have any. This subscription may not be free. The provider might require a minimum length of service. You require a set-top box issued by the cable company, to receive HD content. DishTV and Reliance Communications (BIG TV) are among the satellite TV providers in India who plan to offer HDTV-ready set-top boxes. 3. Blu-ray disk can store over nine hours of high-definition (HD) video on a 50GB disk. 4. A DVD-R can also store up to three hours of HD video content, readable by Blu-ray player, PlayStation 3 video game console or Blu-ray drive installed in a PC, depending on encoder settings. 5. Video game consoles. The latest generation of game consoles is more HD-friendly. While Xbox 360 and PlayStation 3 let you enjoy HD gaming, the Wii will not. The PlayStation 3 also doubles as a Blu-ray movie player. 6. If your computer graphics card supports the standard SVGA resolution, it can be used to output video to an HDTV’s ‘PC input’ jack. 7. The DVI or HDMI interfaces of newer computer graphics cards can be used to output video to an HDTV.

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Components of a typical satellite HDTV system; courtesy Wikipedia

a minimum length of service. An integrated HDTV has an HDTV tuner built into the TV. So you don’t have to purchase an external box to receive HDTV. However, if you subscribe to a cable or satellite service, you may have to purchase their box to receive their HD channel service. In comparison, an HD-upgradable, HD-ready, or HD-compatible TV has all that you need to watch HDTV, but you must add a set-top box to receive HDTV signals. When you are not in a mood to watch television shows, you can connect your HDTV to an upscaling DVD player or a Blu-ray DVD player. In order to take full advantage of this viewing option, your HDTV needs to have either an HDMI or DVI-HDCP connection. Jeremy Hang, division head-Bravia Display, Sony India, explains that upscaling DVD players match the pixel resolution of a standard DVD to that of your HDTV. Although the quality is not the same as watching your DVD in true high-definition, there is a definite improvement in the image quality of your DVDs when played on an upscalw w w. e f y m ag . co m

ing DVD player through an HDTV. In India, Samsung offers two HDDVD players. The Samsung 1080PK is a full-HD DVD player with USB host and HDMI cable included. The Samsung F1080 is full-HD stylish DVD player with HDMI cable included. Kishalay Ray, general managermarketing, Sharp Business Systems (India), says that not many Blu-ray titles are currently available in the Indian market, not making it worth buying at this stage. However, DVDs can output the video at 720p or 1080i resolution via their HDMI jack if it is available in the DVD player as well as in the TV set. If one is a gaming freak, game consoles have been making a slow but steady conversion to high-definition. The latest generation of game consoles is even more HD-friendly. All of the Xbox 360 game titles run at 720p or 1080i, meaning these can look just as good as standard DVDs.

Programming other than HD? HDTV allows programming other than the HD content to be displayed on the screen. There is no drop in quality: On e l e c t ro n i c s f o r yo u • m a r c h 2 0 0 9 • 3 3

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HDTV sets, the native resolution is higher, hence the lower resolution can be easily accommodated without affecting the quality.

Types and cost of HDTV sets HDTVs are available in liquid-crystal display (LCD), plasma, digital light processing (DLP) and liquid-crystal-onsilicon (LCoS) technologies. However, currently the mainstream technologies are LCD and plasma. The cost of HDTV sets varies according to the size and quality of technology. The comparatively high cost of HDTV sets may be a ‘turn off,’ but HDTVs offer excellent picture quality coupled with a big screen experience. Plasma and LCD HDTVs are wallmountable and save space too.

Availability of HDTV sets Most high-end plasma and LCD TVs are HDTV-capable. Sony’s Bravia LCD TVs let you enjoy full advantages of HDTV technology. With slim and stylish designs, these can fit anywhere in your home. Samsung too has a complete portfolio of HDTV and HD-ready LCD TVs: the Full HD LCD Series 6 and 5 and the HD ready Series 4 and 3. In the case of plasma televisions, the Full HD Series 5 and the 3D Ready Series 4 have also been launched in the Indian market.

Issues with HDTV To be able to receive HD content, you need to have an HD-ready TV set or TV set with built-in HDTV tuner, which is comparatively expensive. Also, tradi-

HDTVs are available in liquid-crystal display (LCD), plasma, digital light processing (DLP) and liquid-crystalon-silicon (LCoS) technologies. However, currently the mainstream technologies are LCD and plasma. 3 4 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

Major Contributors to this Report • Tarun Jain, country head-India, Hitachi Home Electronics • R. Zutshi, deputy managing director, Samsung India • Jeremy Hang, division head-Bravia Display, Sony India • Kishalay Ray, general managermarketing, Sharp Business Systems (India) tional SD programmes originally filmed in the standard 4:3 ratio, when seen on an HDTV monitor, will have empty margins to the left and right of the image because 16:9 wide-screen aspect ratio is the standard for digital HDTV. You can choose to fill this unused display area by stretching the SD shows horizontally to fill the screen, but this will only distort the image. Normally, the HDTV transmission is provided through satellite and the same may not be available on free basis. In such a case, you may be required to subscribe to HDTV with the service provider. HDMI, or component video cables, must be used to support high-definition signals. HDMI is an all-digital connection that allows both HD audio and video to pass through a single cable. If you use older video cabling standards like composite or S-Video for connections from a cable box or satellite dish, you will get only an SDTV-quality picture. Another drawback of HDTV is that most of the operators do not fully follow HDTV specifications. So the HD picture quality is usually not as good as promised. Operators tend to use slower bitrates or lower resolution to accommodate more channels within the limited bandwidth, which reduces the video quality. While on an analogue TV, the interference causes the picture to slowly deteriorate from bad to worse, interference in HDTV broadcast will freeze, skip, or display ‘garbage’ information.  The author is a deputy editor at EFY w w w. e f y m ag . co m

careers

Empower Yourself with Power Electronics To continue its growth trajectory, India would need a lot more emphasis on the power sector. So a career in power electronics could prove to be a good take-off for you

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Sudeshna das

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ower is one of those sectors which are showing a promise of growth and expansion amidst the economic slowdown clatter. It may even benefit from the current recession. Its steady rise can be attributed to the immediate need for infrastructure. As corporate majors look to cut costs and increase productivity, the one way they are likely to achieve this is through introduction of a costeffective power solution. In fact, the Target Mission of India ‘Power for All by 2012’ would mean achieving the target of 1000 kWh (units) of per capita consumption of electricity by this period. Hence, if you wish to make your own contribution to the growth story of emerging India, this is one sector that will provide im3 6 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

mense scope and opportunity.

The power story… Let’s first probe a little deep inside India’s growth story. It is well known that the growth of a country can be sustained only if its infrastructure keeps pace with it. Power is the most prominent vertical amongst the infrastructural sectors. According to a midterm report released by Assocham, it topped the list of the most preferred investment sectors with 18.4 per cent of the total infrastructural investment. The current economic recession doesn’t seem to have had any significant impact on job opportunities in the power sector. Commenting on an upbeat employment scenario in the power industry, Sunil Bhatnagar, director, Parker Power System, says, “In times of an economic slowdown

the government looks to pump in more with respect to public expenditure, thus ensuring continuous job creation. For this reason, the power sector has the greatest element of anti-cyclical behaviour, thereby maintaining a healthy growth rate”. Bhatnagar also outlines the new recruitment plan for his organisation. The recruitment trends of PSUs also are in accordance with his comment. NTPC itself has recruited about 1225 professionals last year and is planning to hire more than 1000 engineering and management professionals every year over the coming years. Other power companies—private- as well as public-sector—would also have high manpower requirements in the coming years in view of the growth opportunities present. Large investments from privatesector players like Tata Power, Sterlite Industries, Jindal India Thermal Power and Lanco Group are increasing the chances of new job creation. Moreover, private players in energy management sectors like Conzerv, Enercon and APC are also in hiring mode. Bhatnagar feels that power will be the highest job-generating sector by 2012.

Be a part of the power game Since the power sector comprises a wide range of firms from fairly large and mature companies to the SMBs, the manpower requirement also varies accordingly. The skill requirements are vast and there is room for professionals in product design and development, project engineering, product managew w w. e f y m ag . co m

careers ment, marketing and sales. Professionals who have a superior understanding of electronics, instrumentation, electrical, mechanical and power engineering are required amongst others. Most of the companies have ambitious expansion as well as diversification plans. Companies like NTPC have taken a number of steps to emerge as an integrated power company with presence in coal mining, hydel power generation, power trading and power distribution. Accordingly, there are huge job opportunities for new entrants. While there is still a shortage of quality manpower in the power sector, this seems to be easing out with changing preferences among the fresh engineers from IT to core fields like power and other heavy industries. “We do find that entry-level technical graduates are still charmed by the IT industry, however this trend is changing and bright youngsters are choosing careers in the power industry looking at the long-term growth perspective,” says Anil Kumar Challyil, technical services manager, Arrow Electronics. As an electronics professional you may find your place in the power circuit design section of a solutions providing firm. But opportunities are present even in the maintenance, instrumentation and control sections of any power plant. Work opportunities in the power sector primarily include creation, expansion and enlarging of existing units by utilising both renewable and non-renewable energy sources. Upgradation of the existing capacity through modernisation of equipment and introduction of new technolo-

In the times of an economic slowdown, the government looks to pump in more with respect to public expenditure, thus ensuring continuous job creation. For this reason, the power sector has the greatest element of anti-cyclical behaviour, thereby maintaining a healthy growth rate. —Sunil Bhatnagar, director, Parker Power System gies and better instrumentation may finally open up new job opportunities. Adjunct systems operating with core infrastructure, such as smart energy management systems for commercial and industrial units, may be a right choice for your career. You may ask “How to get an entry ticket?” A decent technical background (ITI, diploma or graduation) along with fundamental knowledge can secure your job ticket. However, for some fields requiring specialised knowledge such as R&D, recruiters look for postgraduates and doctorates. Many employers take campus recruits and train them directly in different areas of power projects to prepare them for various roles in the company. Thankfully, most of the big players in this sector still believe in talent building rather than raiding. This was further confirmed by Neelam Kumar, executive director and head of the department-power electronics, Aplab, who considers talent building as a part of

We do find that entry-level technical graduates are still charmed by the IT industry. However, this trend is changing and bright youngsters are choosing careers in the power industry looking at the long-term growth perspective. —Anil Kumar Challyil, technical services manager, Arrow Electronics

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social responsibility.

Power in your pocket Let’s check whether this field is powerful enough to fill your pocket to a good extent. You could be part of a major project as a junior engineer and grow in 10-12 years’ time to head major projects. Speaking of salary prospects, fresh engineering graduates usually start at Rs 200,000-Rs 350,000 per annum and can grow into either generalist or specialist roles. However, the scene is a little daunting for diploma holders as their starting salary range is usually Rs 150,000 to 200,000 per annum. Even at this moment of economic downturn, the power sector is offering salaries in the range of Rs 500,000 to Rs 1 million per annum for professionals with 5-7 years of experience. It should, however, be noted that for design-related roles, the salary is usually closer to the upper limit. Nonetheless, if you grab an international opportunity, the minimum salary may move up to around Rs 2 million within five years.

Explore the power circuit I believe, up to this point, you have got enough boosters from the opportunities-to-be-grabbed in the power field. So get ready now to explore the power circuit. The power field is specifically suitable for engineering professionals with multidisciplinary interests, such as magnetics and mechanics. Exciting and technically satisfying careers can w w w. e f y m ag . co m

careers We believe in building our talent pool by inducting young professionals and grooming them into competent power professionals through various HR interventions. We have developed a well-structured system for recruiting fresh engineering graduates and diploma holders at the executive level. We recruit people not only on the basis of qualification and skill repertoire but, more importantly, also for their attitude and cultural fit with the company. We even arrange training programmes for students of different technical institutes. —Neelam Kumar, executive director and head of the department-power electronics, Aplab be pursued in the fields of technical marketing, design engineering, project management, and integration and servicing. If you consider the application of power electronics, I must say it is present wherever there is a need for control and conversion of electric power. It may be the tiny converter of your mobile phone in the range of some milliwatts, or a giant one of hundreds of megawatts in a high-voltage directcurrent (HVDC) transmission system. The main metric of power electronics is energy efficiency. And as a professional you are expected to acquire knowledge and skills needed to design practical power electronics systems. If you can achieve it, then control, instrumentation and maintenance of power systems will automatically be on your fingertips. Largely, this is a technical field and so domain expertise and process knowledge are very important. Because of the technology-driven nature of this field, professionals must at all times keep themselves abreast of the latest improvements and technological upgradations that are taking place instead of focusing only on their departmental 4 0 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

concerns. In addition to technical skills, recruiters are also looking for competencies such as interpersonal skills and drive for end results down the ranks. Don’t get nervous. You are not expected to know everything but your learning ability should be high as a lot of training takes place on the job.

Powerful fundamentals Keep in mind that power electronics is primarily concerned with the processing of electrical power using electronic devices. So the key element is the switching converter. All other devices are improved versions of it. In general, a switching converter comprises three ports—power input port, power output port and control. Converters are even classified according to the nature of these ports. For example, in a simple DC-DC converter, the DC input voltage is converted into a DC output voltage by changing its magnitude. The device may perform some additional functions like rectification and inversion of voltage, thereby acquiring the names ‘rectifier’ and ‘inverter,’ respectively. The third port, i.e., control, is required to produce a

well-regulated output voltage in presence of variations in the input and load currents. I have already mentioned the metric of power process. High efficiency is a must for any processing system. The primary reason for this is not to save money on one’s electricity bill or conserve energy. Rather, according to power rule, it is impractical to design a low-efficiency converter which can produce high voltage output. The next thing that you need to know is the application of power electronics. A basic design is modified according to the need of the application. Let’s consider an aerospace application of power electronics. In the power system of an earth-orbiting spacecraft, a solar array produces the main power bus voltage. A DC-DC converter converts the bus voltage into the regulated voltage required by the spacecraft payloads. Battery charge controllers interface the main power bus to the batteries; this controller may also have a DC-DC converter. The power systems of almost all spacecrafts and aircrafts follow this simple scheme. On the other hand, in an electrically driven vehicle, batteries are charged by converters that draw high-factor sinusoidal current from a single-phase or a three-phase AC line. The batteries supply power to the variable-speed AC motors to propel the vehicle. The speed of the AC motor is controlled by the variation of the electrical input frequency. The inverter produces three-phase variable output to control the speed of the motor as well as the vehicle. In some applications, a DC-DC converter steps down the original voltage to a lower level according to the electronics need of the systems. The list of examples may be endless. So instead of mugging up the nitty-gritty of individual systems, try to understand the function of the individual elements, so that you can use them to design the power system of your choice. You may put special emphasis on various common systems to recheck your understanding. A w w w. e f y m ag . co m

careers general understanding of locomotives, battery chargers for telecommunications, inverter systems for applications involving renewable energy generation such as wind and photovoltaic conversion, and also general power utility systems may help you comprehend any unknown power system that you may come across.

Know the elements of power electronics Undoubtedly, one of the things that makes power electronics interesting is its incorporation of elemental concepts from diverse set of fields. As a power electronics professional, you may come across the basics of analogue circuits, electronic devices, control systems, power systems, magnetics, electric machines and even numerical solutions. Thus the practice of power electronics requires a broad understanding of electrical as well as electronics engineering. In addition, there are fundamental concepts which are unique to power electronics and require specialised study. Let’s start with the switching mode. High-frequency switching makes converter modeling the central element of your study. You need to know how to put a converter in equilibrium. The principles of steady-state converter analysis including inductor-volt-second balance, capacitor charge balance and small ripple approximation are of great importance. Try to get a clear idea of how these principles are applied in boost (capable of voltage increase), buck (capable of voltage decrease) and cuk (capable of inverting the voltage priority) converters. For example, ripple approximation greatly simplifies the analysis, especially in a well-designed converter where the switching ripples in inductor current and capacitor voltage are comparatively small with respect to the DC component. Another important element is circuit modeling. You are expected to understand how the DC transformer model is manipulated and solved using conventional circuit analysis 4 2 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

In the IT/ITES segment, with energy efficiency and reduction of operational costs becoming critical business goals, two major trends in data centre infrastructure design are notable today: power efficiency and power distribution.

—Pramod Agashe, COO of APW

techniques. How the models can be refined to account for loss elements such as inductor-winding resistance and semiconductor ‘on’ resistance and voltage drops?

to AC and DC equivalent circuit modelling and resonant conversion and chalk out possible solutions. Last but not the least, update yourself on the latest technological advances in this field.

Realise the field

Prepare for the future challenges

Now that you are aware of the basic elements, it’s time to realise the modus operandi of the actual devices. Switch realisation would be a good starting point. Knowledge about majority carrier devices like MOSFETs and minority carrier devices like BJTs, IGBTs and thyristors is must. Additional knowledge like the operation of unidirectional switches to handle discontinuous conduction mode, may give you an edge over your competitors. Converter circuit is another important matter that needs thorough understanding. Basically, circuit manipulation, transformer isolation along with circuit evaluation and design related skill sets are in high demand. Try to get familiar with converter dynamics and control. The basic understanding of modelling and averaging approaches will be an added advantage. In the next step, you have to perform the actual design job by applying all those techniques and concepts discussed so far. Controller design and input filter design are the two major challenges in this field. Your next challenge is to provide a solution for real-life systems. Go beyond your textbook and enter your own power electronics design laboratory. Try to collect some problems pertaining

Bear in mind that technological advances are meant to increase energy efficiency and reduce operational cost. As a result, the present era is solely dedicated to green energy and energysaving equipment. Understand this hidden demand and keep pace with it. Your final-year project may be on the utilisation of solar energy or wind energy to run a traditional power system—a solar power fuel dispenser, for example. In fact, there are many ingenious ways to improve power efficiency through various innovations. According to industry veterans like Pramod Agashe, COO of APW, traditional power distribution units often fail to cope with today’s high-density computing environments, so designing of efficient power distribution system for data centres may be a good challenge. Any of these real problems may be your next food for thought. Perhaps, at this moment the dilemma about your career prospect is driving you nuts. Boost up your brain. Dig down the power field. It will provide you not only a secure job but the opportunity to be an active part of a nation-building story.  The author is a research analyst cum journalist at EFY w w w. e f y m ag . co m

EFY REPORT

Salary Survey

electronics Industry Maintaining a vigil has the current economic downturn affected the salaries in the Indian electronics industry? Where does it leave employees, as far as prospects of increments in april are concerned? While attempting to figure out the answers to these questions, we surmised that, though employee wages are under the highest scrutiny, it’s time to perform one’s way to a healthy hike 

SudeShna daS

I

f you are earning your bread and butter by working for the Indian electronics industry, it’s time to take up more responsibilities and heighten your performance. Returns at the workplace will now be commensurate with your performance more than ever. On the salary front, it signifies salary structures becoming more performance-based, critical functions taking centrestage and support functions witnessing marginal or no salary

Methodology To assess compensation trends in the Indian electronics industry, EFY’s research bureau collected data on salaries across a range of sectors and companies. The survey covered entry-level professionals, with an average work experience of 0-2 years, to top-level executives with more than 10 years of work experience. The salary data was compiled from 105 companies belonging to these sectors. Since salary data is confidential, names of the companies have not been revealed. The industry ver ticals covered under the survey are consumer electronics, industrial electronics, computer hardware, communication and broadcasting, strategic electronics, components and other specific sectors. Information was collected from small, medium as well as large companies. However, most of the responses came from medium-sized companies. The results of the analysis are presented here.

w w w. e f y m ag . co m

of quarters of 2009, while 67 per cent increase. This, however, should not be foresaw either no imminent change in a cause of concern for the cream of the the numbers or were unsure. crop. An EFY research bureau survey As expected, cost cutting seemed of 105 firms suggests that the huge doto be high on the mestic need and savings-based econoagenda of my of the country help position electronics as one of the few Consumer industries poised for modOthers Electronics erate staffing growth (Value-added 10% in 2009 in spite of the Resellers) global slowdown. So 12% job seekers in the InComponents dian electronics inIndustrial 14% dustry may heave Electronics % a sigh of relief! ics 5 ctron e l 32% E egic ace) The bird’s Strafet nce & Sp

eye view

(De

Communication

Has recession hit In& Broadcasting Computer dian electronics pro15% Hardware fessionals? Of course 12% it has; though not as Verticals dramatically as it has imsurveyed pacted professionals in some most executives. of the other sectors. As recruitment With respect to human resource, this budgets are stretched tighter, many cost-consciousness implies “doing organisations are on the lookout for more while paying less” as companies innovative and cost-effective ways for raise the bar of expectation. They also talent management. The cost head that hinted that the top management was has risen most rapidly in the recent taking a salary cut to help companies years is the ‘pay package.’ Hence, it is tide over. also the one that is being met with the Though India is one of the highest highest level of scrutiny now. paymasters in Asia, the same cannot be The survey found that approxisaid for the electronics industry, parmately 18 per cent of current employticularly in the second half of the fiscal ers in the industry planned to increase year 2008-09. There is a salary freeze in the number of full-time employees most companies. However, the salary in their firms within the first couple e l e c t ro n i c s f o r yo u • m a r c h 2 0 0 9 • 4 3

EFY REPORT what’s on offer? 80 70

Salary range for mid level 80

Entry Level, Tier-I (0-1 year) Entry Level, Tier-II (1-2 years)

68

Responses in %

Responses in %

60

50

48

40 32

30 20 10 0

11

10 5

1-2

40 33 28

2-5

2

0

5-7

Salary range in the unit of Rs 100,000

3

2

0-2

2-5

5-7

7-10

Salary range in the unit of Rs 100,000

7

10+

80

Hike pattern for mid level 80

Fiscal ’08-09 Fiscal ’07-08

70

50 40 32

30

31

26

0

12

11 9

14

10

5

1-5

30

25

20 2

0

0-

40

23

20 10

28

50 40

6-10 11-15 16-20 20+

Hike Pattern for Entry Level in %

0

0

Amt Undecided

10

8

0-

Highest paying job functions Highest Paying Job Functions

33

24 18

Administrative

37 6

Production

Fiscal ’08-09 Fiscal ’07-08

10

Sales & Marketing

41

24 2

Others*

5

0

10

*Other include HR and Finance

20

30

40

Responses in %

4 4 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

6

0

techno-commercial jobs gain favour

R&D

11

50

13

16 10 0

1-5

0

6-10 11-15 16-20 20+

Hike Pattern for Mid Level in %

36

30

26 21

10 0

11 6

0-7

7-10

10-15

15-20

Salary range in the unit of Rs 100,000

20+

Expected pay package

71

60 Responses in %

Responses in %

60

10

Fiscal ’08-09 Fiscal ’07-08

70

40

cases, firms, in fact, reported a decline in salary levels. Availability of surplus manpower as well as negligible profits due to economic sluggishness were the underlying reasons.

hike or freeze? Hike pattern for entry level

50

20

10

8

0

7+

22

21

10

3

0-1

60

50

30

Senior Level (More than 10 years)

70

58

20

18

80

Mid Level, Tier-I (2-5 year) Mid Level, Tier-II (5-10 years)

70

60

Salary range for senior level

Responses in %

Salary range for entry level

0

Amt Undecided

bracket for middle- and senior-level managers has been adjusted. This indicates that companies are now gradually getting their middle-management strategy right and using salary as a tool to retain employees for better leadership roles. Companies seem to have become selective about the kinds of employees they need to retain and have accordingly adjusted the salary quotient. The growth in an average salary for a given position has been nominal in fiscal 2008-09 in comparison to the previous year. In some

Pay packages offered to electronics professionals are proportional to their experience and hierarchy. These also vary with the educational background of the employee, with degree holders attracting higher salary levels within the same band than diploma holders with similar experience. In fiscal 2008-09, due to a dip in the average salary growth, entry-level employees more or less remained in the same salary bands. Take the youngest group of employees, for instance, who have less than one year of experience; 68 per cent of this group continued to draw salaries under Rs 200,000 per annum and 18 per cent stayed within the Rs 200,000-Rs 500,000 bracket. Very few firms hired freshers, with most, such as Cadence Design Systems, providing free internships at best. However, at entry-level, candidates with less than two years of experience typically receive between Rs 100,000-Rs 500,000 per annum as CTC. Employees receiving Rs 200,000-Rs 500,000 per annum get increments as their experience levels increase. In a few cases, the CTC w w w. e f y m ag . co m

EFY REPORT trends in training Training Duration Training Duration

Training Provision Training Provision

98 97

Yes

No

2 3

Fiscal ’08-09 Fiscal ’07-08

72

Upto 15 Days

15-30 Days

54

21 8

Fiscal ’08-09 Fiscal ’07-08

2 million range. This trend reflected in the Rs 2 million+ salary bracket too. This was indicative of the drop in lateral hiring, especially for higher roles.

Hike or freeze?

Considering the current circumstances, should the em38 33 ployees expect ‘increments’ 0 12 in April, or is this word Unpaid Training 90+ Days 62 5 irrelevant in today’s con0 20 40 60 80 100 0 10 20 30 40 50 60 70 80 text? It’s a mixed bag for the Responses in % Responses in % industry. Although only 10 per cent of the respondents reported ‘no hike’ in the survey, only Rs 1 million with 34 per cent a few firms like LG Electronics India people receiving more than actually handed out a definite amount Rs 500,000 a year. The most Flexible Work Options to employees of all levels—it handed noticeable shift in trend was Flexible Work Options out an average increment of 14 per visible in the group having 67 cent to its employees in January 2009. over five years of experience. Yes 58 Most firms were not certain about the While 57 per cent of these Fiscal ’08-09 amount of increments they intended to senior employees drew above Fiscal ’07-08 33 No dole out to staff. For instance, around Rs 500,000 a year, 22 per cent 42 80 per cent firms have decided to limit of employees moved into the the increment to 15 per cent; only 5 per Rs 700,000-Rs 1 million band 0 10 20 30 40 50 60 70 80 Responses in % cent have decided to provide a hike of versus the 10 per cent in the more than 20 per cent. The scene is a 2-5 years of work experience daunting one if you compare it with last year’s, when 28 per cent of the companies were ready to provide more Paternity Duration Paternity Leave Option PaternityLeave Leave Duration than 21 per cent hike for the 87 Paternity Leave Option same level. Upto 15 Days 75 Things, however, pan out 63 Yes differently at the managerial Fiscal ’08-09 13 50 Fiscal ’08-09 15-30 Days 19 Fiscal ’07-08 level with around 71 per cent Fiscal ’07-08 of the respondents stating 37 No 0 50 that increments at this level 30-90 Days 6 were more closely associated 0 10 20 30 40 50 60 70 80 with individual performanc0 Responses in % 90+ Days 0 es. In some companies, like A.V. Systems, top-level ex0 20 40 60 80 100 Responses in % ecutives voluntarily declined to accept pay hikes and even paid a cut from their bonuses to help range. This is a clear indicator of the may even rise to anywhere between Rs their firms stay afloat. efforts made by companies to retain 500,000-Rs 700,000 per annum, dependmiddle-management talent. ing on the candidate’s qualification, Techno-commercial jobs However, the trend changed at skill set, critical aspects of the job and gain favour the senior level, which comprises payment practices of the company. employees with more than ten years For mid-level employees with The existing human resource demand of experience. Twenty-six per cent of around 2-5 years of experience, the in the electronics industry stems prithese employees stayed in the Rs 1.5pay packet ranged from Rs 200,000marily from the junior and middle Paid Training

78

30-90 Days

7

more flexibility?

paternity leave

w w w. e f y m ag . co m

e l e c t ro n i c s f o r yo u • m a r c h 2 0 0 9 • 4 5

EFY REPORT management levels in sales and marketing functions. Given the present economic scenario, firms have an acute focus on conceiving new business as well as capitalising on every possible sales opportunity. The highest paid job function in an organisation, once again, has corresponded with this new focus. Forty-one per cent of companies reported sales and marketing as the highest paid function in their organisations, compared to 24 per cent last year (fiscal 2007-08)—a huge increase of 17 per cent. Furthermore, new-age employers prefer to perceive prospective employees as complete packages, endowed with more than just one specific skill. Even the requirements of a technical job can no longer be satisfied solely by technical competencies; economic and business process knowledge as well as requisite soft skills are heralded as cardinal. Knowledge of enterprise resource planning (ERP) systems, particularly in the field of sales automation, is deemed ‘nice-to-have.’ Surely, companies worldwide are also looking for innovative products as well as new business models to establish a niche for themselves amidst the competitive clutter. In this context, research and development (R&D) is turning out to be a key area where skilled professionals are getting rewarded now more than ever. This is confirmed by Mr Basavaraj, managing director of Neural Systems, when he says, “In a nutshell, it is an ideal situation to invest in long-term plans emphasising on R&D and IP with adequate, talented manpower.” This fiscal, 33 per cent of the respondents identified R&D as their highest paying function, which is 9 per cent higher than last year. Among the sub-segments of the electronics industry, telecom is showing the maximum promise of growth. It doesn’t come as a surprise therefore that R&D and business development activities in this sector offer the highest pay packets for almost all levels of employees. 4 6 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

Training could be the key A lull across the salary front could spell out an opportunity elsewhere. According to 98 per cent of the respondents, improvement in staff training is a valuable way of proofing their businesses for the future. In fact, roughly 78 per cent of the surveyed firms provided paid trainings across all levels to improve internal efficiencies and processes, which is quite promising in comparison with the 38 per cent figure for 2007-08. Apart from the usual expectations pertaining to remuneration, there is also the demand in some quarters, especially from the design engineers, for a flexible work environment. Presently, two-thirds (67 per cent) of the firms surveyed, supported alternative work schedules or flexible timings, along with compressed hours of the week—work for the same number of hours in lesser number of days. Last year, the figure was 58 per cent. It clearly indicates that flexibility is a major strategy of the firms to retain key talent. The scenario may not be so cooperative in matters like paternity leave. Though the proportion of firms (63 per cent) allowing paternity leave was higher than last year (50 per cent), companies seemed to be getting stringent about the number of days leave is granted for. None of the firms allowed more than one month of leave, with more firms (12 per cent higher than 2007-08) stipulating around 15 days only. To sum up, the electronics industry in India appears to be marching right ahead, unfazed by the turmoil around it. While talented individuals in other sectors may be struggling to find stepping stones in times when lay-offs and hiring freezes are the order of the day, the employees in the Indian electronics industry have more than a bright chance to override the recession and kickstart their careers in this industry.  The author is a research analyst cum journalist at EFY w w w. e f y m ag . co m

Manufacture

FLEXIBLE CIRCUITS getting better Circuits that stretch, fold or twist will improve numerous devices. One particular application is biomedical sensors that can be comfortably implanted in the human body 

Dr S.S. Verma

E

lectronics circuits till now are fabricated mostly on hard substrates. This rigidity imposes shape limitations for electronic equipment. Though miniaturisation of integrated circuits has helped to a large extent in giving the desired shape to electronic equipment, much more can be achieved with the latest developments in the fabrication of flexible circuits. Flexible circuitry reduces the size and weight of a finished product. It allows increased circuit density and eliminates bulky connections and wiring. And the added ability to fold the circuit expands the boundaries of design and packaging.

boards, is a technology for assembling electronic circuits by mounting electronic devices on flexible highperformance plastic substrates, such as polyimide. Circuits can be designed in configurations from simple, singlesided conductive paths to complex, high-density, three-dimensional assemblies utilising a variety of fabrication materials from low-cost polyester to mid-range PEN to high-density adhesiveless polyimide Novaclad. Additionally, flex circuits can be screenprinted silver circuits on polyester. Flexible electronic assemblies may be

shape, or to flex during its use.

Developments so far The original method for flexible CMOS circuits comprised a 2- to 3-micrometre circuit layer sitting atop a plastic substrate as much as 100µm thick. It could curve around a small roll of coins. But the new version has a total thickness of only 1.7 µm, including the plastic, which gives it the ability to wrap around a rod whose diameter is roughly 85 µm. In LCD fabrication, glass is used as the substrate. If a thin, flexible plastic or metallic foil is used instead of glass, the entire system can be flexible, as the film deposited on top of the substrate

The underlying technology Flexible electronics, also known as flex circuits, or flex circuit

manufactured using the same components as used for rigid printed-circuit boards, allowing the board to conform to a desired 4 8 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

is usually very thin (of the order of a few micrometres). OLEDs are normally used instead of a backlight for flexible displays, making a flexible organic light-emitting diode display. Flexible solar cells have been developed for powering satellites. These cells are lightweight, can be rolled up for launch and are easily deployable, w w w. e f y m ag . co m

Manufacture which makes them a good match for the application. Bendable, twistable electronic circuits whose performance nearly matches that of conventional CMOS chips, have been reported. These circuits, developed by a team of researchers at the University of Illinois at Urbana-Champaign (USA), are built from ribbons of silicon only a few nanometres thick that are mounted on flexible plastic substrates. The same group or researchers has developed an improved plastic circuit that is not only flexible but also stretchable and foldable. To make it foldable, they looked at the behaviour of everyday objects and decided to make the circuit much thinner. The researchers made plastic circuits by transferring thin ribbons of silicon onto glue-coated plastic using a patterned rubber stamp. But before the ultra-thin silicon layer is applied to the substrate, the plastic is heated, causing it to expand. Once the circuit layer is deposited and chemically bonded to the expanded substrate, the plastic is

5 0 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

allowed to cool and contract. Relaxing the strain causes the circuit layer to buckle and form wavy patterns like the bellows of an accordion. It’s the folds and wrinkles that give the circuit the ability to stretch and bend without breaking. The researchers said that in laboratory tests, the circuits showed no signs of fatigue even after a few hundred stretch-and-release cycles.

Applications abound Flex circuits are often used as connectors in various applications where flexibility, space savings or production constraints limit the serviceability of rigid circuit boards or hand wiring. In addition to cameras, a common application of flex circuits is in computer keyboard manufacturing; today, most keyboards use flex circuits for the switch matrix. Flexible circuits are advantageous in numerous applications: 1. Tightly assembled electronic packages, where electrical connections are required in three axes, such as cameras (static application)

2. Electrical connections where the assembly is required to flex during its normal use, such as folding cell phones (dynamic application) 3. Electrical connections between sub-assemblies to replace wire harnesses, which are heavier and bulkier, such as in rockets and satellites 4. Electrical connections where board thickness or space constraints are driving factors The researchers are entering into partnerships with physicians for development of flexible biomedical devices that can be implanted in the human body in a more comfortable manner; for example, an implantable sensor that will monitor electrical activity in the brain to help predict the onset of epileptic seizures. The device may also work in reverse, sending electric pulses that head off the seizures. This requires a device that will conform to the rippled geometry of the brain.  The author is from Department of Physics, S.L.I.E.T. (deemed to be university), Longowal, District Sangrur (Punjab)

w w w. e f y m ag . co m

cONSTRUCTION

Microcontroller-Based Ring Tone Player

mar

sunil ku



Subhajit Roy

M

obile phone ring tones sound like real audio recordings. It’s not because of the way the melodies are composed, but the protocol behind playing the melody. The ring tone text transfer language (RTTTL) is behind those wonderful lullabies and songs you have on your mobile phone. Basically, a ring tone is the sound made by a mobile phone to indicate an incoming call or text message. Here we present a microcontroller-based ring tone generator.

The basics The lowest resonant frequency of a vibrating object is called its fundamental frequency. Most vibrating objects have more than one resonant frequency and those used in musical instruments typically vibrate at harmonics of the fundamental. A harmonic is defined as an integer multiple of the fundamental Parts List Semiconductors: IC1 - AT89C51 microcontroller IC2 - 7805, 5V regulator T1 - BC337 npn transistor D1-D4 - 1N4007 rectifier diode LED1 - 5mm LED Resistors (all ¼-watt, ±5% carbon): R1 - 330-ohm R2 - 8.2-kilo-ohm R3 - 10-kilo-ohm R4 - 1-kilo-ohm Capacitors: C1 C2, C6 C3 C4, C5

- 1000µF, 25V electrolytic - 0.1µF ceramic disk - 10µF, 16V electrolytic - 22pF ceramic disk

Miscellaneous: X1 - 220V AC primary to 9V, 500mA transformer XTAL - 11.0592MHz crystal LS1 - 8-ohm, 1W speaker

5 2 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

frequency. A cylindrical air column with both ends open vibrates with a fundamental frequency. Each end of the column must be an antinode, with one node at the centre for the air motion. Therefore if ‘λ’ is the wavelength of the sound produced by an open cylindrical air column, its length ‘L1’ Fig. 1: Fundamental will be: frequency vibration in an open air column L1 = λ/2 (λ/4+ λ/4)

So λ =2L1 Frequency n1 = V/λ (where ‘V’ is the velocity of sound) By putting the value of ‘λ,’ we get: n1 = V/2L1 If length is half, then: Frequency n2 = V/L1 n1/n2 = (V/2L1) × (L1/V) = 1/2 or n1 = 2n2 Thus halving the length doubles the frequency, i.e., frequency n1 is created with one octave higher (2n1). If the length is made quarter of the original, the frequency becomes 4n1, i.e., two octaves higher. If n1 is octave 1, then n2 is octave 2, then n3 is octave 3, and so on. If the length is doubled, the frequency is halved. That is, the freFig. 2: PWM signal, where Ts1, ts1 and D1 are the time period, half time quency becomes period and duration of note 1, while Ts2, ts2 and D2 are the time period, half time period and duration of note 2 n1/2, which is one octave lower. In music, freTable I quency n1 is called a Nokia RTTL Frequencies (Hz) note. The pitch of a (For Octave 4 to Octave 7) piano key or guitar No. Octave=4 Octave=5 Octave=6 Octave=7 string is described by the note. 1 A 220.000 440.000 880.000 1,760.000 According to 2 A# 233.082 466.164 932.328 1,864.655 musical frequency 3 B 246.942 493.883 987.767 1,975.533 conventions, there 4 C 261.626 523.251 1,046.502 2,093.005 are twelve notes in 5 C# 277.183 554.365 1,108.731 2,217.461 all, namely, A, A#, 6 D 293.665 587.330 1,174.659 2,349.318 B, C, C#, D, D#, E, F, 7 D# 311.127 622.254 1,244.508 2,489.016 F#, G and G#, where 8 E 329.628 659.255 1,318.510 2,637.020 ‘# ‘sign indicates a 9 F 349.228 698.456 1,396.913 2,793.826 sharp note. 10 F# 369.994 739.989 1,479.978 2,959.955 According to 11 G 391.995 783.991 1,567.982 3,135.963 Nokia RTTTL spec12 G# 415.305 830.609 1,661.219 3,322.438 ifications, note A w w w. e f y m ag . co m

Best-in-Class Dimming Performance. High Efficiency. High Performance, TRIAC Dimmable LED Driver National’s industry-leading TRIAC dimmable offline LED driver solution is perfect for any application where an LED driver must interface to a standard TRIAC wall dimmer. National’s new TRIAC dimmable LED driver delivers a wide, uniform dimming range free of flicker, best-in-class dimming performance, and high efficiency—all while maintaining ENERGY STAR® power factor requirements in a typical application.

© 2009, National Semiconductor Corporation. National Semiconductor,

, and PowerWise are registered trademarks. All rights reserved. EA0608-C1

Online design tools Reference designs Application notes

Full Range Dimming Capability

LED Lighting Solutions Website:

national.com/led Technical Support Website:

national.com/support

National’s TRIAC dimmable LED driver offers 100:1 full range dimming capability, going from full light to nearly imperceptible light in a continuous range without being extinguished, and maintains a constant current to large strings of LEDs driven in series off of a standard line voltage.

Easy To Use National’s TRIAC dimmable LED driver enables a direct replacement of incandescent or halogen lamp systems that are currently interfaced to a TRIAC dimmer without having to change the original infrastructure or sacrifice performance. In addition, the new TRIAC dimmable LED driver is available in WEBENCH® LED Designer to allow for easy and quick design in.

Uniform Dimming Without Flicker National’s TRIAC dimmable LED driver allows masterslave operation control in multi-chip solutions which enables a single TRIAC dimmer to control multiple strings of LEDs with smooth consistent dimming, free of flicker.

cONSTRUCTION Table II

Values in Hex to be Loaded to Timer 1 (Oscillator Frequency 11.0592 MHz) Notes

a

a#

b

c

c#

d

d#

e

f

f#

g

g#

Octave 4: A4=220 Hz

F7D1

F847

F8B6

F91F

F982

F9DF

FA37

FA8A

FAD9

FB23

FB68

FBAA

Octave 5: A5=440 Hz

FBE9

FC23

FC58

FC8F

FCC1

FCEF

FD1B

FD45

FD6C

FD91

FDB4

FDD5

Octave 6: A6=880 Hz

FDF4

FE12

FE2D

FE48

FE60

FE78

FE8E

FEA3

FEB6

FEC9

FEDA

FEEB

Octave 7: A7=1.76 kHz

FEFA

FF09

FF17

FF24

FF30

FF3C

FF47

FF51

FF5B

FF64

FF6D

FF75

Octave 8: A8=3.52 kHz

FF7D

FF44

FF8B

FF92

FF98

FF9E

FFA3

FFA9

FFAE

FFB2

FFB7

FFBB

Fig. 3: Circuit of microcontroller-based ringtone generator

with octave 5 has a frequency of 440 Hz (refer Table I): A5 = 440 Hz So we get: A6 = 880 Hz (A5x2) A7 = 1760 Hz (A6x2) The space between two consecutive octaves like A5 and A6 is divided into eleven equally spaced parts on the logarithmic scale. Thus there are twelve equally spaced notes per octave: A5, A#5, B5, C5, C#5, D5, D#5, E5, F5, F#5, G5, G#5 and then A6 starts. RTTTL is a simple text-based format that you can use to create ring tones. An RTTTL file is made up of a single string divided into three sections separated by colons (:). In the example of a Happy Birthday song given below: d=4, o=5, b=125:16c, 32p, 32c, 32p, 8d, 32p, 8c, 32p, 8f, 32p, e, 16p, 16c, 5 4 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

32p, 32c, 32p, 8d, 32p, 8c, 32p, 8g, 32p, f, 8p, 16c, 32p, 32c, 32p, 8c6, 32p, 8a, 32p, 8f, 32p, 8e, 32p, 8d, 32p, 16a#, 32p, 32a#, 32p, 8a, 32p, 8f, 32p, 8g, 32p 1. The first section is the name of the RTTTL melody, i.e., ‘Happy Birthday Song.’ 2. The second section defines the default values for the file. There are three categories of default values: duration (d=4), octave (o=5) and beat per minute (b=125). 3. The third section describes the melody. It is a set of notes separated by a comma. The notes are given in the following format: Duration (dn) Note Octave 8 c 6 where ‘dn’ is the duration of the present note. If either the duration (dn) or octave

is not specified for a particular note, the default values are assumed. After getting the notes, you must calculate the duration for which a note is to be played: Number of notes per second to be played (N) = 60/beats per minute (b) =60/125 Net duration D in seconds for which a note is to be played = No. of notes per second × (Default note duration)/ (Duration specified for the current note) = N×d/dn = (60/125) ×(4/8) = 30/125 So to play music, all you need to do is to get the RTTTL ring tone of the particular music, then read its note and generate the frequency for the calculated duration (D). “If the note is dotted; for example, ‘2b’ (here ‘b’ denotes note, not beats per second), the duration is made 1.5 times, so that D=1.5D.” Generation of PWM frequency. Since we are dealing with digital systems, we need to generate PWM (pulse-width-modulated) signals from port pin P2.0 of the microcontroller. A PWM signal consists of ‘high’ w w w. e f y m ag . co m





cONSTRUCTION period calculation as follows: 1. Timer 0 for calculating the duration (D) 2. Timer 1 for calculating the half time period (ts) The CPU takes certain number of clock cycles to execute an instruction. The simplest instruction takes a single byte of code and executes in one machine cycle. The standard 8051 machine cycle is equal to twelve oscillator cycles. We have used a 11.0592MHz crystal. Fig. 4: Actual-size, single-side PCB for the microcontrollerSo time period = based ring tone generator 1/(11.0592×106) = 0.0904 µs Time period of a machine cycle = 0.0905×12 = 1.085 µs Timer 0. Timer 0 is a 16-bit timer that is used for duration ‘D.’ It is loaded with value DC00H. Therefore the number of machine cycles taken by the timer before it is reset=FFFF–DC00+1=2400H= 9216 in decimal. Therefore time taken ‘t’ = 9216×1.085 µs = 0.001 second So after timer 0 is set, it will take 0.001 second to reset. For 1-second duration, Fig. 5: Component layout for the PCB the timer needs to be set (P2.0 = 1) and ‘low’ (P2.0 = 0), i.e., the 1/0.001=100 times. bit remains ‘high’ for a certain period For duration ‘D,’ timer 0 needs to of time and ‘low’ for the same period be set Dx100 times. of time (refer Fig. 2). Timer 1. The half time period is Time period of the note (Ts) = ‘ts.’ 1/frequency of note Therefore the number of machine Therefore, cycles needed = ts/1.085 µs Duration of ‘high’ bit (time for If the value of the timer is ‘x,’ then which P2.0 is ‘1’)= Ts/2 = ts1 (half-time FFFF–x+1 = ts/(1.085x10-6) period) From this equation, the value of ‘x’ Duration of ‘low’ bit (time for can be calculated. which P2.0 is ‘0’)= Ts/2 = ts1 (half-time 1’s and 0’s are continuously generperiod) ated from port pin P2.0 at an interval So you need to use two timers for of ‘ts’ seconds alternatively until duraduration D and half-time period ‘ts.’ tion ‘D’ (in seconds) completes (refer Use one timer to generate 1’s and 0’s Table II). at a time interval of ‘ts’ and the other Circuit description timer to interrupt the PWM signal after time interval D. Fig. 3 shows the circuit of the microWe have used two timers for timecontroller-based ring tone generator. 5 6 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

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cONSTRUCTION At the heart of the circuit is microcontroller AT89C51. It is a low-power, high-performance, 8-bit microcontroller with 4kB Flash programmable and erasable read-only memory. It has 128 bytes of RAM, 32 input/output (I/O) lines, two 16-bit timers/counters, a five-vector two-level interrupt architecture, on-chip oscillator and clock circuitry. The 11.0592MHz crystal provides the basic clock frequency to the microcontroller. Port pin P2.0 of the microcontroller provides the ring tone melody signal for speaker LS1. Transistor BC337 is used for amplification. The power-‘on’ reset signal for the microcontroller is generated by the combination of capacitor C3 and resistor R2. Switch S1 provides manual reset to the microcontroller. The 230V AC mains is stepped down by transformer X1 to deliver the secondary output of 9V, 500 mA. The transformer output is rectified by a full-wave bridge rectifier comprising diodes D1 through D4,

filtered by capacitor C1 and regulated by IC 7805 (IC2). Capacitor C2 bypasses the ripples present in the regulated power supply. LED1 acts as the power-‘on’ indicator and resistor R1 limits the current through LED1. An actual-size, single-side PCB for the microcontroller-based ring tone generator is shown in Fig. 4 and its component layout in Fig. 5.

$mod51 FLAG EQU 07FH SPEAKER EQU P2.0 BEGIN: ORG 0000H AJMP MAIN

RET PLAY_NOTE: CONTINUE: CLR A MOVC A,@A+DPTR MOV R0,A INC DPTR CLR A MOVC A,@A+DPTR MOV R1,A INC DPTR CLR A MOVC A,@A+DPTR MOV R2,A INC DPTR CLR A MOVC A,@A+DPTR MOV R3,A INC DPTR RET ACTION: CLR TR0 CJNE R1,#0,DO2 CLR FLAG SJMP DO3 DO2: DEC R1 DO3: MOV TH0,#0DCH MOV TL0,#00H SETB TR0 RET SONG: ; HAPPY BIRTHDAY ; R0 R1 R2 R3

Software The program plays “happy birthday to you” in RTTTL ring tone format using the microcontroller AT89C51. The source program, written in Assembly language and assembled using assembler ASM51, is self-explanatory and easy to understand. Initialise timer 0 and timer 1 as 16-bit timers with predetermined value. When you start timer 0, the data pointer register is loaded with memory address labeled as ‘SONG.’ After playing the current note, the control jumps to the next note and it starts playing.

This process continues until the end of music data is reached. Thereafter, it starts playing the music from the beginning. Nokia RTTTL ringtones can be downloaded from the following websites: 1. http://www.2thumbswap. com/members/tones/nokia/tones_ nokia_latest.html 2. http://nokiatone.ifrance.com/ nokiatone/rtttf.htm 3. http://ringtones.frostzone.com/ index.htm 4. http://arcadetones.emuunlim. com/files.htm RTTL ringtones can also be tested on the computer, the software for which can be downloaded from the link ‘http://arcadetones.emuunlim. com/files/nokring_full.zip.’ (Refer “A Cell Phone Player Embedded in Microcontroller” by Manoel Gomes de Andrade for details.) EFY note. The source code and other relevant files of this article are included in this month’s EFY-CD.

ringtones.asm

ISR: ORG 000BH LCALL ACTION RETI ORG 0050H MAIN: MOV TMOD,#00010001B ; MOV IE,#82H ; MOV TH0,#0DCH MOV TL0,#00H SETB TR0 MOV DPTR,#SONG MOV R0,#02 LOOP1: ACALL PLAY_NOTE CJNE R0,#02,CARRY_ON SJMP MAIN ;end of music has been detected so start again CARRY_ON: ACALL PLAY SJMP LOOP1 PLAY: CLR EA SETB FLAG SETB EA RUN: JNB FLAG,STOP DO: CJNE R0,#0,START SJMP RUN START: MOV TH1,R2 MOV TL1,R3 SETB TR1 HERE: JNB TF1,HERE CLR TF1 CLR TR1 CPL SPEAKER SJMP RUN STOP: CLR SPEAKER

5 8 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

DB 1, 12, 0FCH, 08FH ;R0=1 indicates there is a note to played DB 0,6,0,0 ;R0=0 indicates there is no note to be played DB 1,6,0FCH,08FH DB 0,6,0,0 DB 1,24,0FCH,0EFH DB 0,6,0,0 DB 1,24,0FCH,08FH DB 0,6,0,0

DB 1,24,0FDH,06CH DB 0,6,0,0 DB 1,48,0FDH,045H DB 0,12,0,0 DB 1,12,0FCH,08FH DB 0,6,0,0 DB 1,6,0FCH,08FH DB 0,6,0,0 DB 1,24,0FCH,0EFH DB 0,6,0,0 DB 1,24,0FCH,08FH DB 0,6,0,0 DB 1,24,0FDH,0B4H DB 0,6,0,0 DB 1,48,0FDH,06CH DB 0,24,0,0 DB 1,12,0FCH,08FH DB 0,6,0,0 DB 1,6,0FCH,08FH DB 0,6,0,0 DB 1,24,0FEH,048H DB 0,6,0,0 DB 1,24,0FBH,0E9H DB 0,6,0,0 DB 1,24,0FDH,06CH DB 0,6,0,0 DB 1,24,0FDH,045H DB 0,6,0,0 DB 1,24,0FCH,0EFH DB 0,6,0,0 DB 1,12,0FCH,023H DB 0,6,0,0 DB 1,6,0FCH,023H DB 0,6,0,0 DB 1,24,0FBH,0E9H DB 0,6,0,0 DB 1,24,0FDH,06CH DB 0,6,0,0 DB 1,24,0FDH,0B4H DB 0,6,0,0 DB 1,48,0FDH,06CH DB 2,0,0,0 ;R0=2 indicates end of music  END

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cONSTRUCTION

PC-BASED WIRELESS STEPPER MOTOR control 

V. Mariyappan

S

tepper motors find lots of applications in process control, machine tools and robotics. Especially in robotics and process control, it is necessary to control the stepper motor from a remote place. Here we describe how to wirelessly control a stepper motor from a remote place by using RF modules. For this wireless stepper-motor control system, you need to design and develop the required hardware and software. The parallel port of the PC is used to control the direction of the stepper motor at the transmitter side. RF interface is used instead of IR to overcome all the drawbacks of the IR interface. The PC

Table I

Output Power and Current Drain w.r.t. VCC VCC

O/P

Current

5V DC

–0 dbm

1.0 mA

12V DC

+9 dbm

3 mA

Table II

Technical Specifications of RF Receiver RX-433 Description Working voltage

Value 4.5V-5.5V

Bandwidth

12 MHz

Sensitivity

–103 dbm

Data rate

4800 bps

Max. data rate

9600 bps

Standby current Antenna

1, 2 mA Whip, strip line or helical

signals are transmitted from the RF transmitter and received by the RF receiver.

Circuit description Fig. 1 shows the block diagram for PC-based wireless control of a stepper motor. The signals from the parallel port of the PC are interfaced to the RF transmitter through an encoder. The encoder continuously reads the status of the relay switches, passes the data to the RF transmitter and the transmitter transmits the data. At the receiving end, the RF receiver receives this data and gives it to the decoder. The decoder converts the single-bit data into four-bit data and presents to the stepper-motor driver. Now, the driver performs the corresponding action, i.e., it rotates the stepper motor clockwise or anticlockwise. Remote control. For remote control, we have used the Holtek encoder-decoder pair Fig. 2: Pin configuration of HT12E and HT12D. of the rf Both of these are 18-pin transmitter module DIP ICs. Operation of Holtek HT12E and H T 1 2 D . HT12E and HT12D are CMOS ICs with a working voltage of Fig. 3: Pin configuration of the r a n g e rf receiver module 2.4V to 12V.

Fig. 1: Block diagram for PC-based wireless control of a stepper motor

6 0 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

mar

sunil ku

Parts List Semiconductors: IC1 - HT12E Holtek encoder IC2 - 7806, 6V regulator IC3 - HT12D Holtek decoder IC4 - CD40106 hex inverter IC5 - ULN2003 Darlington array T1-T4 - BC547 npn transistor T5 - BC548 npn transistor D1-D4 - 1N4148 switching diode D5-D10 - 1N4007 rectifier diode TX1 - TX-433 RF transmitter RX1 - RX-433 RF receiver LED1 - 5mm LED Resistors (all ¼-watt, ±5% carbon): R1 - 1-mega-ohm R2-R5 - 10-kilo-ohm R6-R9 - 1.2-kilo-ohm R10 - 1-kilo-ohm R11 - 47-kilo-ohm R12 - 3.9-kilo-ohm R13 - 470-ohm Capacitors: C1, C3 C2 C4 Miscellaneous: BATT.1 BATT.2 S1, S2 DIP-SW1, DIP-SW2

- 100µF, 16V electrolytic - 0.1µF ceramic disk - 10µF, 16V electrolytic - 9V battery - 6V, 4.5Ah battery - On/off switch

- 8-way DIP switch - 25-pin D-type male connector

Encoder HT12E has eight address and another four address/data lines. The data set on these twelve lines (address and address/data lines) is serially transmitted when transmit-enable pin TE is taken low. The data output appears serially on DOUT pin. It is transmitted four times in succession. The data consists of differing lengths of positive-going pulses for ‘1’ and ‘0,’ the pulse width for ‘0’ being twice the width of the pulse for ‘1.’ The frequency of these pulses may lie between 1.5 and 7 kHz depending on the resistance value between OSC1 and OSC2 pins. The internal oscillator frequency of decoder HT12D is 50 times the oscillator frequency of w w w. e f y m ag . co m

cONSTRUCTION

Fig. 4: Transmitter circuit for wireless stepper motor control

encoder HT12E. The values of timing resistors connected between OSC1 and OSC2 pins of HT12E and HT12D, for the given supply voltages, can be found out from the graphs given in the datasheets of the respective chips (included in this month’s EFY-CD). The resistance values used in the

circuits are chosen here for approximately 3kHz frequency of the encoder (HT12E) at Vcc of 9V and 150 kHz of the decoder (HT12D) at Vcc of 5V. The HT12D receives the data from the HT12E on its DIN pin serially. If the address part of the data received matches the levels on A0 through A7

Fig. 5: Actual-size, single-side PCB for the transmitter circuit 6 2 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

pins four times in succession, the valid transmission pin (VT) is taken high. The data on pins AD8 through AD11 of the HT12E appear on pins D8 through D11 of the HT12D. Thus the device acts as a receiver of 4-bit data (16 possible codes) with 8-bit addressing (256 possible channels).

Fig. 6: Component layout for the PCB shown in Fig. 5 w w w. e f y m ag . co m

cONSTRUCTION

Fig. 7: Receiver-cum-decoder circuit for wireless stepper motor control

Fig. 8: Actual-size, single-side PCB for the receiver-cumdecoder circuit

Fig. 9: Component layout for the PCB shown in Fig. 8 6 4 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

Once the frequency of the pair is aligned, then on ground of any data pin of the encoder, LED1 of the decoder should glow. You can also check the transfer of data on pins AD8 through AD11, which is latched to D8 through D11 pins of the decoder once TE pin is momentarily taken low by grounding it through diodes D1 through D4. RF transmitter and receiver. RF transmitter and receiver modules from Alpus India, Mumbai, have been used for RF remote control. The RF transmitter TX-433 is AM/ASK type. Its features include: 1. 5V-12V single-supply operation 2. On-off keying (OOK)/amplitude shift keying (ASK) data format 3. Up to 9.6kbps data rate 4. +9dBm output power (about 200m range) 5. SAW-based architecture 6. A 45cm wire is adequate for the antenna The output power and current drain for Vcc of 5V and 12V are

shown in Table I. The pin configuration of the transmitter module is shown in Fig. 2. The RF receiver RX433 is a 433MHz module. Its pin configuration is shown in Fig. 3, while the technical specifications are given in Table II. Transmitter. Fig. 4 shows the circuit of the transmitter for wireless stepper motor control. The receiver address to be transmitted can be set with the help of 8-way DIP switch SW1. When any of the switch contacts is open the respective pin will be at logic 1, and when any of the switch contacts is closed the respective pin will be at logic 0. The data pins are pulled high via resistors R2 through R5. When pin 2 of the parallel port goes high, transistor T1 is driven into saturation and relay RL1 energises. Pin 10 (AD8) goes low through relay RL1 contacts and a ‘0’ is sent at that data position, while other data pins represent logic-1 state. The logic circuitry at the receiver-decoder end decodes the data appropriately for controlling the stepper motor. An actual-size, single-side PCB for the transmitter circuit (Fig. 4) is shown in Fig. 5 and its component layout in Fig. 6. Receiver and decoder. Fig. 7 shows the circuit of the receiver-cum-decoder for wireless stepper motor control. Assuming that identical address is selected on the encoder and decoder, when any of the data pins of the PC’s parallel port on the transmitter side is low, the corresponding data pin of the decoder will go low. The data outputs (D8 through D11) of HT12D are fed to inverters N1 through N4, which, in turn, are connected to driver ULN2003. The low output of ULN2003 drives the stepper motor. When any w w w. e f y m ag . co m

cONSTRUCTION T5 into saturation and LED1 lights up. An actual-size, single-side PCB for the receiver-cum-decoder circuit (Fig. 7) is shown in Fig. 8 and its component layout in Fig. 9.

Software

Fig. 10: Main screen of wireless stepper motor control

data is received, valid transmission (VT) pin goes high to drive transistor

The software program for the user interface to control the stepper motor is written in ‘C’ language. The signals are generated by the outport( ) function. The speed of rotation of the stepper motor can be varied by changing the argument of the delay( ) function. Direction of rotation (clockwise or

anticlockwise) depends on the switch function. When the program (WSTEPPER. C) is loaded and run, the screen shows the welcome message. Pressing any key will lead to the main screen shown in Fig. 10. The main screen displays three messages. Pressing ‘c’ key rotates the stepper motor in clockwise direction, while pressing ‘a’ key rotates the stepper motor in anti-clockwise direction. The program can be terminated by pressing ‘q’ key. EFY note. The source code and other relevant files of this article are included in this month’s EFY-CD.

WSTEPPER.C /*PC BASED WIRELESS STEPPER MOTOR CONTROL*/ #include<stdio.h> #include #include<dos.h> void main() { void dub(void); char ex[26]={“Programmed by V.MARIYAPPAN”}; int i; char ex1[22]={“Programming Language: C”}; int j; char ex2[28]={“Operating system: Windows 98”}; int k; char ex3[39]={“PC BASED WIRELESS STEPPER MOTOR CONTROL”}; int l; clrscr(); for(l=0;l<39;l++) { textcolor(14);gotoxy(21+l,9); cprintf(“%c”,ex3[l]); delay(50); } sound(1900); delay(500); nosound(); delay(100); for(i=0;i<26;i++) { textcolor(11);gotoxy(27+i,16); cprintf(“%c”,ex[i]); delay(30); } for(k=0;k<28;k++) { textcolor(9);gotoxy(26+k,18); cprintf(“%c”,ex2[k]); delay(30); } for(j=0;j<22;j++) { textcolor(9);gotoxy(29+j,20); cprintf(“%c”,ex1[j]); delay(30); } sound(1800); delay(500); nosound(); getch(); dub(); } void dub(void) { int i; char ex[29]={“For any clarification con-

6 6 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

tact”}; int j; char ex1[31]={“[email protected]”}; int k; void clock(void); void anty(void); char ch; clrscr(); textcolor(14);gotoxy(20,6); cprintf(“PC BASED WIRELESS STEPPER MOTOR CONTROL”); textcolor(11); gotoxy(24,14); cprintf(“FOR CLOCKWISE ROTATION PRESS ‘c’”); textcolor(11);gotoxy(22,16); cprintf(“FOR ANTICLOCKWISE ROTATION PRESS ‘a’”); textcolor(9);gotoxy(31,20); cprintf(“FOR EXIT PRESS ‘q’”); ch=getch(); switch(ch) { case ‘c’:clock();break; case ‘a’:anty();break; case ‘q’: clrscr(); { for(j=0;j<29;j++) { textcolor(9);gotoxy(27+j,14); cprintf(“%c”,ex[j]); delay(30); } for(k=0;k<31;k++) { textcolor(9);gotoxy(26+k,15); cprintf(“%c”,ex1[k]); delay(30); } outport(0x0378,0); textcolor(14);gotoxy(1,25); cprintf(“Press any key”); getch(); exit(0); } default: clrscr(); textcolor(12);gotoxy(33,1 4); cprintf(“WRONG KEY PRESSED”); for(i=0;i<5;i++) { sound(1000); delay(100); nosound(); delay(100); } dub(); }

getch(); } void clock(void) { int p=0x0378; char e; clrscr(); textcolor(14);gotoxy(31,12); cprintf(“CLOCKWISE DIRECTION”); textcolor(9);gotoxy(1,25); cprintf(“Press any key to stop”); do { outport(p,1); delay(200); outport(p,2); delay(200); outport(p,4); delay(200); outport(p,8); delay(200); outport(p,0); sound(1000); delay(200); nosound(); } while(!kbhit()); getch(); dub(); } void anty(void) { int p=0x0378; char e; clrscr(); textcolor(14);gotoxy(30,12); cprintf(“ANTI CLOCKWISE DIRECTION”); textcolor(9);gotoxy(1,25); cprintf(“Press any key to stop”); do { outport(p,8); delay(200); outport(p,4); delay(200); outport(p,2); delay(200); outport(p,1); delay(200); outport(p,0); sound(2000); delay(200); nosound(); } while(!kbhit()); getch(); dub();  }

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first look!

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first look!

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rechargeable batteries. The rotating iPod docking station disappears for storage and protection during transit. The moulded handle makes it easy to carry this iPod accessory from place to place. A custom remote easily controls the system and basic iPod functions including playlist navigation. The auxiliary input lets you play other portable sources too.

Portable DLP Projectors The BenQ CP270 and MP727 are good for business travelers

BenQ’s new projectors aim at providing optimal solutions for frequent traveling professionals. The 1.5kg Commuter Series CP270 is ideal for business travelers and small offices. It projects at native XGA (1024x768) resolution and features a high brightness of 2000 ANSI lumens with a high contrast ratio of 1000:1. Further, its 30-second quickcool feature allows the projector to cool fast even after long usage hours. Targeted at the industrial sector, the MP727 high-brightness projector is equipped with a host of features that suit the needs of small- and mediumsize businesses. This intelligent and automatic projector gives high-quality output in almost any condition. The projector has a brilliant 4300 ANSI lu-

Price: CP270: Price not available MP727: Rs 168,000 plus tax

mens, which makes it perform in blackout conditions to well-lit environments. Contrast ratio is as high as 3500:1. For multimedia users, the MP727 projector has HDTV compatibility, integrated 3-watt speaker and HDMI 1.3 (with HDCP). The universal audio remote lets you easily adjust the volumes of all audio devices connected to the projector, such as external speakers, DVD player and notebook. w w w. e f y m ag . co m

first look!

Tabletop Desktops The HP CQ 2000 series desktops weigh only 3.5 kg and come loaded with Compaq Bhasha vernacular interface The Compaq Presario CQ 2000 series of Hewlett Packard (HP) is a sleek, ecofriendly machine at an affordable price of around Rs 18,990. Designed for the modern households, this small device can easily replace your music system and DVD player as you can attach it to your LCD monitor and speakers or simply enjoy online video clips on YouTube. The CQ 2000 also comes with the Compaq My Bhasha software—a communication enabler providing vernacular interface. With a 6-in-1 digital media reader and USB drives, all you need to do is plug-in, sit back

and do what you need to.  The CQ 2000 is Energy Star certified for being energy-efficient. Price: Rs 18,990 plus taxes

Ultra-Short-Throw Projector Hitachi’s CP-A100 projector eliminates shadowing effects The presenter’s shadow on the screen during a presentation and the projector glare which blinds the presenter, have been the two major problems with the projectors.  Hitachi has developed an ultra-short-throw projector that overcomes these problems. The dramatic reduction in throw distance (capability to project an image onto a 203cm screen from a distance of merely 24.8 cm) and the introduction of a high-angle proPrice: Rs 125,000 7 2 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

jection capability means that the Hitachi CP-A100 projector can be mounted very close to the screen. This brings additional convenience, viewing comfort and safety while eliminating shadowing effects common with conventional projectors. The high-quality 3LCD panel provides crisp, flicker-free images at XGA resolution. Brightness level is 2000 lumens in normal mode and 2500 lumens in bright mode. The contrast ratio is 400:1. In whisper mode the projector has quietness of 28 dB—the same as that of a guest room in a hotel!

Airtel IPTV Service Airtel’s digital TV interactive offers telephone, broadband and TV on a single line Bharti Airtel has launched the digital TV interactive—its Internet protocol television (IPTV) service. With this, Airtel delivers the triple-play advantage of telephony, broadband and entertainment service to its customers. The triple-play service will be initially available to customers in Delhi, Gurgaon and Noida. Airtel digital TV interactive claims to bring many firsts to the TV viewing experience: Interactive 2.0 offers a completely interactive experience including the freedom of ordering pizzas and movie tickets from the comfort of your TV set. Time-shift TV transforms TV into a two-way experience, allowing you to pause and

Entry cost: Rs 3999

rewind live TV as well as auto-record and store favourite programmes for seven days. Movie-on-demand with 100 blockbuster titles means you can view movie of your choice at any time.   The entry cost for the Airtel digital TV interactive subscriber is Rs 3999 only. This includes a one-time activation cost, Internet connection with modem and landline, and settop box. w w w. e f y m ag . co m

Buyers’

Guide

Personal

Music Players Personal music players are available in a multitude of formats, sizes and feature sets. So you are bound to get confused in selecting the right one. Here are the guidelines for a smart buy

iPod touch

Uma Bansal

P 

ersonal music players are of two types: analogue and digital. Analogue players are long-play gramophone record/cassette type, while digital players can be uncompressed (capable of CD playback) or compressed (capable of MP3/WMA/AAC playback). The quality of analogue music is excellent to start with but deteriorates over the usage period of time. Also, mechanical devices are used for playback, which are bulky and prone to wear and tear. Portability is lesser.

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There is loss of quality with each subsequent copy. Storage becomes headache when collection grows bigger. On the other hand, the quality of digital music varies from average to excellent depending upon the conversion format and compression technique used, quality and the technological advancement of replay device. Consistency of music quality is very high. Playback devices are compact to ultracompact. And storage is no issue for compressed music.

What’s available in digital? When going for a personal music player, you have a choice between

dedicated CD players, MP3-enabled mobiles and portable MP3 players. Of these, MP3 players are ubiquitous today. Portable MP3 players. These are continually evolving from simple audio players to complex multimedia devices. Most can show digital photos transferred from your computer, sometimes with accompanying music. Many can also play movies and music videos downloaded from the Web. Among the flurry of models available, Apple’s iPods account for majority of MP3 players sold. Apple’s success rests in part on its creation of a self-contained digital entertainment e l e c t ro n i c s f o r yo u • m a r c h 2 0 0 9 • 7 3

Buyers’

Guide

system. Its online iTunes store offers a large library of online video content, supplementing its dominance over online music sales. MP3 players score high over mobiles on the following counts: 1. The sound clarity of portable MP3 players is far superior to MP3enabled mobiles. 2. The battery life of MP3 players can be up to 35 hours, without requiring recharging even for weeks. 3. Some MP3 players come with very high ease of use while searching for the songs or storing and retrieving different album arts. There are hundreds of MP3 players to choose from, all with their own advantages. Major brands of MP3 players include Apple, Creative Labs, iRiver, Philips, RCA, Samsung, SanDisk, Sony and Toshiba. Brands from smaller companies are also available in the market. MP3 playback has also been incorporated into handheld products like CD players, cell phones and personal digital assistants (PDAs). Digital MP3 players can be differentiated based on the type of memory used: Flash and hard-disk. Flash-memory type. Players that use

MP4 players, also known as personal video players, let you view video clipping/video films apart from listening to audio. These score over MP3 players in that they have a larger display screen and can support more formats. flash memory are extremely sturdy and robust for usage on the move. The reason is these have no moving parts, so you can take them for jogging and your music won’t skip. They are the smallest and lightest players, measuring no bigger than a pack of playing cards. Flash memory is available up to 64 GB. In India, you can get up to 16GB only. Most users prefer flash memory-based music players. MP3 players can also double as USB memory sticks. Some may have expansion slots to add more memory via card slots on the player. However, MP3 players are little expensive in terms of per GB cost compared to hard-disk type. A good example of MP3 players is Sony’s Walkman. Catering to music fanatics with countless CDs at home, Sony’s collection of MP3 Walkman is able to shrink your multitude of CDs into just one small device. The flash

memory digital music player range does not only look good, it can accommodate unlimited music transfers or even serve as a data storage device. Some of the latest Walkman video MP3 players include NWZ-E436F/P and NWZ-E435F/B. Both of these are compact and light-weight, come with FM tuner, support high-quality video playback and have a user-friendly interface for easy operation. The 4GB NWZ-E436F/P is available for Rs 6490, while the 2GB NWZ-E435F/B is priced at Rs 4990. Hard-disk memory type. These players use mechanical parts and are prone to usage issues when used while skipping or dropped down. They are larger and heavier than flash players. The memory capacity cost per GB is low. In India, you can get up to 160GB hard-disk player. It can store up to 40,000 songs. Hard-disk MP3 players like Apple iPods lead the portable audio world in terms of storage. The limiting factor is usually price. In general, buy as large a memory as you can afford, but if you only need the space to hold a thousand tunes, there is no reason to spend the extra money for a 40GB player. Portable MP3 players can be further differentiated based on the formats: 1. MP3-only audio players. Branded good-quality MP3-only players are available for Rs 1500 to Rs 6000. Chinese unbranded versions can come for as less as Rs 600-Rs 2000. 2. MP4 players. MP4 players, also

Philips personal audio player

7 4 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

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rs e n n i W

of Diwali Dhamaka

1st Prize Plasma TV

Mrs Poonam Kapoor, Director, EFY Group, presenting the Plasma TV to

Ms Deepalaxmi, the First Prize Winner

2nd Prize MP4 Player

1. Mr Vilas Katke, Mumbai 2. Mr Earnest Selva Paul, Secunderabad 3. Mr Rishi Kumar, Delhi 4. Mr Vijay Kumar, Bangalore 5. Sarada Instt of Tech. & Science, Khammam

3 Prize rd

Travel Bag

1. 2. 3. 4. 5. 6. 7. 8. 9.

Mr Viraj Patel, Mumbai Ms Shruti Verma, New Delhi Ranganathan Engineering, Coimbatore SRA Systems Ltd, Chennai Mr Sri Balaji M, Bangalore Mr Ravinder Reddy Tumu, Bodhan Mr Anuraj Anand, Pathanamthitta Sloka Telecom Pvt Ltd, Bangalore Akashganga AME India Pvt Ltd, Chennai 10. Mr V Sundaresan, Chennai 11. Mr Darshan Kumar, Punjab 12. Mr Om Prakash Kanoongo, Mumbai 13. Mr Jaisingh Varma, Mumbai 14. Mr Niranjan Sahoo, Visakhapatnam 15. Mr K Parthiban, Tiruchirappalli

16. Mr N M Irshath, Kayalpatnam 17. Mr Vismay Buche, Hyderabad 18. VVM's Shree Damodar College, Goa 19. Mr P R Mantry, A P 20. Dr Bhagwati Prasad, Span, Mumbai 21. Mr Sivaji Mopidevi, EATON, Pune 22. Mr Kishor Narkhede, Secunderabad 23. Industrial Training Instt, Pune 24. St Mira's College For Girls, Pune 25. Dr P K P Mahamood, Kerala 26. Mr Steve Antony Sequeira, Karnataka 27. Indira Shiva Rao Polytechnic, Karnataka 28. V N Krishnaswamy Naidu, Coimbatore 29. Mr Narendra K Sangame, Karnataka 30. Mr A Sudarshan, Virudhunagar 31. Mr Ramkumar R, Coimbatore 32. Government Industrial, Chittoor 33. Mr Biju Kumar J, Kerala 34. Mr T Vetrivel, Tamil Nadu 35. Fr Nijo, Principal, Kerala

36. Perfect Communications, Ludhiana 37. Rajeev Electronics Pvt Ltd, New Delhi 38. The Vazir Sultan College of Engg., Khammam 39. Mr R K Maharana, Orissa 40. Mr Sajith Kumar V R, Bangalore 41. Mr Pundalik Sutar, Mumbai 42. Siemens Enterprises Communications Pvt Ltd, New Mumbai 43. Mr Sunil R, Kerala 44. Safa College Of Engg & Tech, Andhra Pradesh 45. Mr B N V Prasad, Andhra Pradesh 46. Mr Venkatesh V, Chitradurga 47. Mr B L Desai, Karnataka 48. Mr Krishna Prasad Y Bhat, Karnataka 49. Mr Biswanath Das, Kolkata 50. Sivanandha Mills Ltd, Coimbatore 51. Shriram Instt of Engg Technology, Maharashtra 52. Ms Lalita Bhardwaj, Sonepat 53. City Power Conversion, Secunderabad 54. Mr Syan Kumar R, Cochin 55. Mr Vinod Kumar P P, Kerala 56. Mr Pankaj Bhagat, Hyderabad 57. Mr Manoj Rakhyani, Madhya Pradesh 58. VLB Janakiammal Polytechnic College, Tamil Nadu

6. Great Lakes Instt. of Management, Chennai 7. Mr Rahul Singh Kotesa, Goa 8. Collage of Engineering, Maharastra 9. Bharathiyar Centenary Memori, Tamil Nadu 10. Ms S Padhmalakshmi, Chennai

59. Mr A.M. Panduranga, Karnataka 60. Mr Manuvel Nadar M, Kerala 61. Mr Raghavendra C, Karnataka 62. Mr Bharat H Karani, Mumbai 63. Mr V R Aneesh, Kerala 64. Mr K Sathianarayanan, Chennai 65. Sri Sankara Arts & Science College, Tamil Nadu 66. Mr Dinesh Malyiya, Rajasthan 67. Mr Labh Singh, Bathinda 68. Info Instt of Engg, Coimbatore 69. J R Communications & Power Controls, Trichy 70. Al-Madina College of Computer Science, Andhra Pradesh 71. Ms Vijayalakshmi K, Bangalore 72. Mr Deependra Kumar Rajput, Bangalore 73. Mr Arvind Kumar, Kaithal 74. Mr Ramakrishna V, Bangalore 75. Centre for Environment Education, Ahmedabad 76. Dhanalakshmi Srinivasan Engineering College, Tamil Nadu 77. Sandur Polytechnic, Karnataka 78. Mr Kirit P Budh, Gujarat 79. Mr Sadiq Hussain, Dibrugarh 80. Mr Kirit P Budh, Gujarat

81. Vimala College, Trichur 82. Rotary Midtown Library, Rajkot 83. Ms Snehal Joshi, Gujarat 84. Mr Komel Bhojani, Pune 85. The ICFAI Institute of Science & Technology, Jaipur 86. Mr Sachin G. Gune, Pandharpur 87. Mr Z Jatin Shah, Mumbai 88. R P Gogate College of Arts & Science, Maharashtra 89. St Edumund's College, Meghalaya 90. Amity Electronics Corporation, Mathura 91. Mr Bhaskar N Chhibber, Pune 92. Sangamner Nagarpalika Arts, Maharashtra 93. Mr Charan Jit Singh, New Delhi 94. Mr Sumanta Sarkar, Gwalior 95. Mr Sanjay V M, Bangalore 96. Sree Narayana College of Technology, Kerala 97. Mr Satish Kumar Bidwaik, Mumbai 98. Mr Suresh S, Kerala 99. Sri Venkata Ramaswamy, Karnataka 100.Mr Tufan Sharma, Maharasthra

EFY Enterprises Pvt Ltd, D-87/1, Okhla Industrial Area, Phase 1, New Delhi 110 020 Ph: 011-26810601-03; Fax: 011-26817563, E-mail: [email protected], website: www.efyindia.com

Buyers’

Guide

known as personal video players, let you view video clipping/video films apart from listening to audio. These score over MP3 players in that they have a larger display screen and can support more formats than MP3 players. Like MP3 players, these may come in hard drive or flash memory versions. Good-quality branded MP4 players are priced between Rs 2000 and Rs 18,000. MP4 players from Humx are available in screen sizes ranging from 7.1 cm (2.8 inches) to 7.6 cm (3 inches), with built-in capacity of 1 GB, 2 GB or 4 GB. There are four models in all: MP252, MP342, MP432 and MP522. All are MLC flash memory-based and support rechargeable Li-ion battery, 20 FM channels, numerous audio and video formats (MP3, WMA, WAV, DAT, VOB, MP4, MOV, ASF, ASX and WMV), e-book and game function. The MP252 and MP432 also support RM/RMVB, AVI, FLV, 3GP and MPG formats. CD players with ‘MP3’ compatibility. Other than flash-memory and hard-disk portable players, many of today’s portable CD players also let you play digital music saved on disks. But these don’t support the copyrightprotected formats from online music stores. Controls and displays are as good as in portable MP3 players, and

Humx MP4 player

7 8 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

you can group songs on each disk according to artist, genre and other categories. A CD, with its 650 to 800MB storage capacity (about 150 to 200 songs), can hold more than ten hours of MP3format music at the standard CD-quality setting. You can create MP3 CDs using the proper software and your PC’s CD burner. Cell phones. An increasing number of phones have built-in MP3 players—some with controls and features that rival standalone players. Some cell-phone providers let subscribers download music over their networks. Song capacity is often determined by the size of the external memory card, as well as the phone manufacturer, carrier or music provider.

What to look for in an mP3 player? Size, weight and design. Let’s face it, aesthetics go a long way. Just like mobile phones, MP3 players have become fashion accessories. The player should also be lightweight, compact and easy to operate with one hand. Some MP3 players are so small that these can hang off a keychain, while others will barely fit in your hand. Tomonori Moroda, division head, personal audio, Sony India, says that the smallest players are great for

workout routines, jogging or even clipping to a shirt lapel for everyday use. Larger MP3 players are fantastic for playing video and enjoying music, but these are typically much more expensive and can be considered niche products with far fewer accessories. Appearance aside, a player’s design also goes hand in hand with its size and weight. This can vary a lot between devices, the lightest weighing around 20 gm. Hard-disk players tend to be much heavier than their flash counterparts due to the weight of the hard disk and the larger battery required. Lightweight and sleek flash-memory-based players are the current style statement. Whichever MP3 player you choose, make sure you’ll be comfortable using the device. Look for a display that is easy to read. Also, the controls should be easily accessible. Audio format. MP3 (Moving Pictures Expert Group Audio Layer 3) is just one of the many formats you can play on digital audio players. It is a digital audio format encoded on computer from a source such as CD. The files are compressed but retain near-original sound quality. Most MP3 players can play one or more other compressed audio formats too, such as Advanced Audio Coding (AAC), Ogg Vorbis (OGG) and Microsoft’s Windows Media Audio (WMA). Make sure that your player is compatible with MP3, WMA and AAC at least. Here’s how these audio formats differ: WMA. A Windows Media Audio file is about half the size of an MP3 file, but offers similar sound quality. If you want to fit as many songs as possible onto your audio player, look for WMA compatibility. A 60GB WMA-compatible MP3 player can store up to 30,000 songs in WMA format—or just 15,000 in MP3. MP3Pro. It has better audio quality than MP3, but isn’t widely popular among manufacturers. w w w. e f y m ag . co m

Buyers’

Guide Pros and cons of MP3 players Pros • Most MP3 players are compact and light • With the lack of moving parts, unlike CD players, there is no chance of skip, whether the user is jogging, on a bumpy car ride or cycling • These can store large collections of music, thus usually supporting your playlists on a single device • Often contain extra features such as radio Cons • More expensive than older-format devices • Some storage formats (such as MP3) could be superseded • Encoding files and transferring data can be time consuming and require other devices such as PCs —Tomonori Moroda, division head, personal audio, Sony India

OGG. Ogg Vorbis format has excellent sound quality and is gaining popularity. AAC. Dolby’s Advanced Audio Coding format is used in Apple iPods and can be downloaded from Apple’s Internet music store ‘iTunes.’ WAV. It’s uncompressed audio, just as you would hear on a standard CD. Storage capacity and format. The storage capacity of an M3 player

depends on the memory used. As mentioned earlier, in India you can get up to 16GB flash player or up to 160GB hard disk player. A 1GB player can store around 250 songs (16 hours of music). Hard disk-based players can store a fairly large collection of songs, but are expensive and not as sturdy as flash memory-based players. Some players may use memory

Sony NWZ-B130F series

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Buyers’

Guide

cards such as MultiMediaCard (MMC), SecureDigital, CompactFlash and MemoryStick (for Sony) for storage. In case you have a handheld gadget like cellphone or digicam using memory card, make sure that you choose an MP3 player that accepts that particular card too. Battery type, replaceability and life. Most players come with an inbuilt rechargeable battery. When you connect it to your computer or laptop, the battery gets charged automatically. After full charging, it can play audio for up to 15-30 hours and video for up to 2-6 hours depending upon the brand and model of player you are using. Battery life of no less than 12 hours for music and four hours for video is a good bet. Rechargeable batteries last up to three years depending on the usage. A few players have battery bays for AA or AAA batteries. Generally, users don’t prefer the recurring cost of replaceable batteries. Display. The display lets you easily select your music by artist, album or genre. It is also useful when you’re looking for a particular radio station. In audio formats, the displays available are 2.5cm black & white (capable of one to three lines), 2.5cm colour and 3.8cm OLED. In video formats, the screen size varies from 3.8 cm (1.5 inches) to 8.9 cm (3.5 inches) with 262,000 colours. The screen type varies from TFT to QVGA/WQVGA. The resolution also varies from 128x128 to 240x400. Hard disk players may come with a colour screen for song info and for viewing your digital photos. Music store. Online music buying is not very prevalent in India but is a normal practice in West. The benefits of online music buying are: 1. Offers instant, legal access to hundreds and thousands of songs 2. Allows you to preview/prelisten and purchase individual songs instead of the whole album 3. Legal source complies with copyright laws 8 0 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

4. More consistent and higher-quality metadata Software bundled with the player. Good bundled software is a great bonus as the quality of your recordings depends on the quality of software you use. Media player is the software used for playback of multimedia files. Typical features of such a software are: 1. Rips music from a CD and saves it as an MP3 file 2. Burns MP3 file to CD or DVD 3. Organises MP3 files with ID3 data tags 4. Allows you to create your own playlists It’s important that the media player software is supported by the operating system of your computer. Some common software are iTunes, Real Player, Windows Media Player, Quick Time and KM player. Other extra features (like FM tuner, voice recording, games, etc). Most MP3 players come with FM tuner. FM comes very handy for current news update and change in music entertainment. Lots of college students are using voice recording feature very innovatively. They record lectures in the classroom and prepare notes at leisure. This helps them focus on the content at the time of lectures. A 1GB MP3 player can support voice recording of up to 65 hours, while a 2GB player can support up to 135 hours. FM tuner and voice recording are standard features on all Philips digital players. Also, high-end players from Philips come with inbuilt noise cancellation feature. Accessories. Flash-based MP3 players need speakers and amplifiers for loud sound. Lots of docking systems are available for these music players. The small and sleek players can be worn on the body as ornaments. The related accessories are available in various shapes and sizes. Philips provides high-definition earphones with noise-isolation technique.  The author is a deputy editor at EFY w w w. e f y m ag . co m

circuit

ideas

Triple Power Supply 

Sandip Trivedi and P.D. Lele

T

his low-cost, multipurpose power supply fulfils the requirements of almost all laboratory experiments. Nonetheless, it can be easily fabricated by hobbyists. A single transformer is used to build this triple power supply. Regulator IC LM317 generates variable power supply of 1.25 to 20V, 1A. The dual ±12V, 1A power supply is generated by regulators 7812 and 7912. Similarly, dual ±5V, 1A power supply is generated by regulators 7805 and 7905. ‘On’/‘off’ switches (S2 through S4) select the required power supply. Variable power supply is used to study the characteristics of devices. Fixed +5V power supply is used for all digital, microprocessor and microcontroller experiments. Dual ±12V power supply

edi

s.c. dwiv

is used for op-amp-based analogue circuit experiments. Fig. 1 shows the circuit of the triple power supply, while Fig. 2 shows the pin configuration of the regulators used in the circuit. Transformer X1 steps down the mains power to deliver the secondary output of 18V-0-18V. The transformer output is rectified by full-wave bridge rectifier BR1, filtered by capacitors C1, C2, C3, C7 and C8, and regulated by IC1 through IC5. Regulator IC1 (LM317) provides variable voltages (1.25 to 20V), while IC2 and IC4 provide regulated +12V and –12V, respectively. The output of IC2 is fed to regulator IC3 (7805), which provides fixed +5V. Similarly, the output of IC4 is fed to regulator IC5 (7905), which provides fixed –5V. Capacitors C4 through C6, and C9 through C11, are used for further filtering of ripples

in positive and negative regulated power supplies. LED1 glows to indicate that +5V is available, while LED2 indicates that –5V is available. Switch S1 is used for mains ‘on’/ ‘off’. Using switches S2 through S4, any of the three supplies can be independently turned off when not required in a particular experiment. This reduces unnecessary power dissipation and increases the life and reliability of the power supply. Since the circuit uses three terminal regulators, only capacitors are required at the input and output. The use of few components makes the circuit very simple. The three terminal regulators have heat-sink provision to directly deliver 1A output current. To ensure the maximum output, do not forget to

HEAT SINK IN

S2 = FOR VARIABLE VOLTAGE

3

IC1 LM317 2

S2

S3 = FOR +12V AND +5V

1

R1 120

ADJ.

S4 = FOR –12V AND –5V C3 0.1µ

S1-S4 = ON/OFF SWITCH

+1.25 TO 20V

GND

VR1 2.2K POT

S1 ON/OFF SWITCH

+12V

HEAT SINK IN

F1 1.5A FUSE

OUT

X1

L 230V AC 50Hz N

1

S3

IC2 7812

3

HEAT SINK OUT

IN

1

IC3 7805

C1 1000µ 35V

OUT

2

2

GND

BR1 W04

3

GND

C2 0.1µ

R2 330

C5 10µ 16V

C4 100µ 25V

+5V

C6 0.1µ

BR1 W04

LED1

GND X1 = 230V AC PRIMARY TO 18V-0-18V, 1.5A SECONDARY TRANSFORMER

C7 1000µ 35V

C10 10µ 16V

C9 100µ 25V

C8 0.1µ GND 2 S4

IN

–5V

GND 1

BR1-W04 1.5A, BRIDGE RECTIFIER

C11 0.1µ

R3 330

IC4 7912

LED2

1 3

HEAT SINK

2 OUT

IN

IC5 7905

3

OUT

HEAT SINK

–12V GND

Fig. 1: Tripple power supply

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circuit

ideas

Fig. 2: Pin configurations of regulators

use heat-sinks for the regulators. The three-terminal regulators are almost non-destructible. These have inbuilt protection circuits including the thermal shutdown protection. Even if there is overload or shorting of the output, the inbuilt overload protection circuit will limit the current and slowly reduce the output voltage to zero. Similarly, if the temperature increases beyond a certain value due to excessive load and heat dissipation, the in-built thermal shutdown circuit will reduce the output current and the output voltage (gradually) to zero. Thus complete protection is provided to the circuitry. Assemble the circuit on a generalpurpose PCB and enclose in a box as shown in Fig. 3. The step-by-step procedure to build the triple power supply for the laboratory follows:

Fig. 3: Proposed cabinet for power supply

1. Collect all the components shown in the circuit diagram. 2. Connect switch S1, fuse, transformer and mains cord to the assembled PCB as well as the box. 3. Keep the multimeter in DC voltage range (more than 25V DC) and measure the DC voltage across capacitors C1 and C7 (1000 µF, 35V). This voltage should be around 18V×1.41=25 to 26V DC. Check both positive and negative voltages with respect to ground. 4. It is advisable to use three-wire mains cable and plug. If you are using any metallic box, earthing wire/pin of the mains plug should be soldered to the body of the metallic box using an

earthing tag. 5. If the 18V-0-18V transformer is replaced with 15V-0-15V transformer, the output voltage of the variable supply using LM317 will be correspondingly lower. 6. If proper voltages are available, go to step 7. Otherwise, check the connections. 7. Connect variable regulator LM317 to the circuit and check 1.25V to 20V output by varying the 2.2-kiloohm linear potentiometers. 8. Now connect ICs 7812, 7912, 7805 and 7905 to the circuit and check their output voltage. 9. Connect terminals, potmeter, switches and indicator LED on the front panel of the box and complete the connections. Close the box by using screws. Precaution. At the primary side of the transformer, 230V AC could give lethal shocks. So be careful not to touch this part. EFY will not be responsible for any resulting loss or harm to the user. 

unique Water Pump Controller edi

s.c. dwiv

A

R4 12K

S1 ON/OFF SWITCH

B 3 +

D. Mohan Kumar

H

ere is a simple solution for automatic pumping of water to the overhead tank. Unlike other water-level indicators, it does not use probes to detect the water level and hence there is no probe corrosion problem. It has no direct contact with water, so the chance of accidental leakage of electricity to the water tank is also eliminated. Two important advantages of the circuit are that the water 8 2 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

7

IC1 µA741 2

–

4

R6 220

6

T1 BC558

D1 1N4148

C1 220 25V VR1 10K PRESET

12V DC

+

N/O R5 12K

LED4

D2 1N4007 C2 470µ 25V

MOTOR



N/C RL1

230V L AC N 50Hz RL1 = 12V, 1 C/O RELAY

Fig. 1: Water pump controller w w w. e f y m ag . co m

circuit

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Fig. 2: Sensor circuit

level never goes below a particular level and no modification in the water tank is required. Fig. 1 shows the circuit of the waterpump controller. The circuit uses an LDR-white LEDs assembly to sense the water level. It forms a triggering switch to energise the relay for controlling the pump. The LDR-LEDs assembly (shown in Fig. 2) is fixed on the inner side of the cap of the water tank without making contact with water. The light reflected from the water tank is used to control the resistance of LDR1. When the water level is high enough, light from the white LEDs (LED1 through LED3) reflects to fall on LDR1. This reduces the resistance of LDR1, increasing the voltage at the non-inverting input (pin 3) of IC1. IC1 is used in the circuit as a voltage comparator. Resistors R4 and R5 form a potential divider to fix half of supply voltage to the inverting input of IC1. Normally, when the water tank is full, LDR1 gets more of reflected light because the distance between the water

Fig. 3: Sensor assembly

level and the face of LDR1 is minimal. When white light falls on LDR1, the voltage at the non-inverting input (pin 3) of IC1 increases and its output goes high. This high output makes pnp transistor T1 non-conducting and the relay remains de-energised. LED1 also remains ‘off.’ Since the water-pump power supply is connected to the normally-open (N/O) contacts of relay RL1, pumping is stopped. When water level falls, the amount of light reflected to LDR1 decreases and its resistance increases. This reduces the voltage at pin 3 of IC1 and its output goes low. This low output from IC1 makes transistor T1 conduct. Relay RL1 energises to close the N/O contacts and the motor starts pumping water. LED1 glows to indicate the

pumping of water. Assemble the circuit on a generalpurpose PCB and enclose in a suitable cabinet. Solder the white LEDs-LDR1 assembly on a separate PCB and use a separate power supply for it. Mount LEDs behind the LDR. Otherwise, light from the LEDs will affect the working of the circuit. Connect LDR1 to the main circuit board at ‘A’ and ‘B’ points. Fix the LEDs-LDR1 assembly on the inner side of the water-tank cap as shown in Fig. 3. Orient the LEDs and the LDR such that when the water tank is full, the light emitted from the LEDs and reflected from the water surface falls directly on LDR1. The distance between the upper level of water and the LEDs-LDR setup should be minimal, ensuring that water doesn’t touch LDR1. Otherwise, the circuit will not function properly. By using more white LEDs, this distance can be increased. Cover the LDR with a black tube to increase its sensitivity. You can fix the main unit at a convenient place and connect it to the LEDs-LDR assembly through wire. Select the relay according to the horsepower (HP) of the water pump. After arranging the setup (with maximum water in the tank), adjust VR1 until LED1 stops glowing. In this state, the relay should de-energise. When the water level decreases, the relay automatically energises to connect mains to the motor and it starts pumping water. 

THREE-COMPONENT FLASHER 

T.A. Babu

S

ince this flasher system uses only three components, it is relatively easy to build and install. It can be used for signal flashing, hazard warning and alternate flashing. At the heart of this circuit is a single-pole double-through (SPDT) contacts relay (see Fig. 1). It is a 12V, 400-ohm, single-changeover (1C/O), PCB-mounted relay with contacts curw w w. e f y m ag . co m

edi

s.c. dwiv

rent rating of 5A. The working of the circuit is very simple. Initially, bulk capacitor C1 charges through resistor R1 and the bulb filament. When capacitor C1 charges, relay RL1 energises and

Fig. 1: Simple flasher circuit e l e c t ro n i c s f o r yo u • M a r c h 2 0 0 9 • 8 3

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Fig. 4: Circuit of alternate flasher Fig. 2: Circuit of turn signal flasher

throws its contacts to the other position. Capacitor C1 holds the contacts until there is enough charge to keep the relay energised. Bulb L1 (12V, 5W) glows for a while through the N/O contacts of the relay. When the charge in the capacitor ceases, the relay contacts return to their initial normallyclosed position. The charging cycle repeats to give a flashing effect in the bulb. The ‘on’ time of the flasher is controlled by the

Fig. 3: Circuit of hazard-warning flasher

charge stored in the capacitor. The ‘off’ time is controlled by the discharging time of the capacitor. The signal flasher is a four-bulb system as shown in Fig. 2. Two bulbs are used at the front of the vehicle and the other two at the back of the vehicle. The primary function of the ‘turn’ signal flasher is to flash the lamps when the ‘turn’ signal switch is activated to

the left or right. The circuit of the hazard-warning flasher is shown in Fig. 3. Used in vehicle lighting systems, it flashes all the four bulbs when hazard-warning switch S3 is ‘on.’ During hazard warning, switch S2 can be in the left or right position. The alternate flasher circuit is shown in Fig. 4. It flashes the lamps alternately when the system is activated. This type of flasher is typically used in emergency vehicles and school buses. 

In-Car Food and Beverage Warmer edi

s.c. dwiv



Ashok K. Doctor

T

his is a very useful device for those who are frequently on the move. It will keep your tea, coffee or food warm while consuming little power. The circuit is simple. The ubiquitous timer 555 is used as a free-running astable multivibrator. Diodes 1N4148 are con8 4 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

nected in reverse direction to facilitate maximum variation of the duty cycles.

Power transistor T1 is Darlington type with 5A capacity and output of more w w w. e f y m ag . co m

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than 60 watts. The chosen discrete components assure fixed frequency of 1 Hz (approximately) at pin 3 of timer IC1 (555). Resister R1 and potmeter VR1 (1-mega-ohm) allow adjustment of the duty cycle. The higher the duty cycle, the higher the output of the heater. You can connect up to five 10W heating elements in parallel, totaling 50

watts. The consumption of current will be significantly less if fewer coil elements are connected in parallel through toggle switches S2 through S4. Each of these switches has a 6A rating. Assemble the circuit on a generalpurpose PCB. Mount power transistor TIP120 on a thick heat-sink. Isolate the circuit from the heating elements using

only two wire connections. Use wires that can carry more than 6A current. Fix the coil elements below an aluminium or steel rectangular plate which is at least 1mm thick. Do not forget to insulate the heating plate from the elements. Use the car battery for the power supply with a proper currentcarrying-capacity wire. 

WHITE LIGHT FOR REFRIGERATOR 

Uday ShEnde

N

ormally, the refrigerator lights are yellow in colour and go bad very often. If you want a long-lasting white light for your refrigerator, this circuit is especially for you. The circuit is easy to install inside the refrigerator. Also, it consumes very little power compared to the traditional yellow bulb.

The circuit is transformerless and uses a capacitor for providing the power supply to the white LEDs. Mains input is fed to capacitor C1 and resistor R1, rectified by a bridge rectifier comprising diodes D1 through D4, and filtered by capacitor C2 to provide sufficient voltage to drive the white LEDs. Resistor R2 limits the current flowing through the LEDs. The circuit uses 16 bright

Smart Hearing Aid Devrishi Khanna and Rohit Modi



N

ormally, hearing aid circuits consume battery power continuously once they are switched on. The circuit given here saves battery power by switching on the sound amplifier section only w w w. e f y m ag . co m

when sound is detected. The sensitivity of the detection section and the ‘on’ time duration of the sound amplifier circuit can be set by the user. Also the circuit uses only a single condenser mic for sound detection and amplification. As is clear from the above, this hearing aid consists of a condenser

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white LEDs in 2×8 parallel-connection configuration. Assemble the circuit on a general-purpose PCB along with 16 white LEDs. Connect the LEDs in series with resistor R2. Take out the two wires from the usual bulb connection and connect to the circuit. After connecting the supply wires, wrap electrical tape around the wires properly. Enclose the entire PCB (excluding LEDs) in a plastic box and wrap the box properly with tape to seal it against moisture. 

o

sani the

microphone, earphone, and sound detection and amplification sections. The sound detection section employs a quad op-amp IC LM324 (IC1(A)) and a timer NE555 (IC2). The sound signal received at the mic is pre-amplified by transistor BC549 (T1). The voltage e l e c t ro n i c s f o r yo u • M a r c h 2 0 0 9 • 8 5

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at its collector is fed to the inverting terminal (pin 2) of op-amp IC1(A), which is used as a comparator. The reference voltage (Vref) at the noninverting terminal (pin 3) of IC1(A) is set using preset VR1. The preset is also used to control the sensitivity of the sound signals received by the circuit. The output from pin 1 of IC1(A) is fed to the trigger input (pin 2) of timer NE555, which is configured in monostable mode. When sufficient sound signal strength is detected at the base of transistor T1, the pulsating voltage at its collector exceeds the reference voltage at pin 3. As a result, output pin 1 of IC1(A) goes low. The low output from

8 6 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

IC1(A) triggers the NE555 timer and its output goes high for a preset duration. R4 and C2 are the timing components for setting the time duration. The high output of the timer is directly used as the power source for the sound amplifier section. The sound amplifier section is built around transistors T2 through T5. The last amplifier stage T5 (pnp transistor BC558) drives the earphone. The sound signal received from the mic is fed to the non-inverting pin of the second op-amp of IC1(B) which is wired in unity follower configuration. The unity follower mode resolves the problem of impedance mismatch which would have occured if the output of the mic

is fed directly to amplifier stage. The output from pin 7 of IC1(B) is fed to the base of transistor T2. The weak signal received at transistor stage T2 is further amplified by transistors T3, T4 and T5. An earphone to listen to the sound is connected between the collector of T5 and ground. It is recommended to use a mono earphone with volume control attached. With 9V DC supply, when sound is detected through the mic, the amplifier section is automatically triggered and the current consumption of the circuit is about 96 mA. When the amplifier circuit is ‘off,’ the circuit draws a current of about 6 mA only, thus saving considerable amount of battery power. 

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Software

section

LAN-based Online Exam 

Rahul Bagai

U

sing this program, examinations can be conducted online for students of various subjects in schools and colleges. The examination result along with solutions to the questions is displayed at the end of the exam. The questions are randomly generated from a bank of questions stored in a database maintained by the administrator. These are multiple-choice with four possible answers. Each question is worth one mark. The student has to select one subject at a time, so the questions will be on that topic only. For example, a subject may have many chapters and multiple questions related to that chapter are stored in the database. From here, only 15 questions from selected chapter are generated randomly for the test. The software has the facility to store many chapters under one particular subject. The exam paper will be made up of some questions taken from every topic/chapter. The administrator can change this content by adding new topics and changing the number of questions for each topic. He can add any number of questions and topics. The student can answer each question by clicking a radio button, so from four possible answers only one answer is selected per question. After answering all the questions, the student needs to click a button at the bottom. All the answers by the student are stored in the PC and the marks scored displayed.

to the client. The question database is stored at the server end. The client accesses the database from the server machine and displays the contents on its output screen. The project includes three Java source code files: ServerOnline.java,

Fig. 1: First page on the client PC

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ConnectDatabase1.java and ClientOnline.java. There is an Online Exams.mdb Microsoft Access database file which contains the list of questions and answers. The detailed questions are saved in GIF (graphic interchange format). The ‘Questions and Answers’ folder contains the images of the multiple-choice questions. There are also some other images and MP3 files included for the project. All the image and MP3 files are linked to the MS Access database through configurations as explained under the testing steps.

Operation of the program Fig. 2: Instructions for the students

Fig. 3: Screenshot to select a chapter

Software program The program is developed using J2SE software development kit (JDK1.6) and MS Access application on a Windows XP machine. It is designed on a client-server architecture which operates only when the server provides services

o

sani the

Fig. 4: Screenshot of the online question

1. As soon as the client program is started, a Java applet page as shown in Fig. 1 loads into its output screen. Here the student can select his class (10th or 12th) and the subject (physics, chemistry, biology or mathematics) for which he wants to give the exam. In the database for this project, we have included sample questions on biology and mathematics only. As soon as a radio button corresponding to a particular subject is selected using mouse, the client machine needs to connect to the database stored in the server machine. So click ‘Connect to Database’ button to start the test. 2. Next, the instruction page is loaded. It displays some instructions to be e l e c t ro n i c s f o r yo u • m a r c h 2 0 0 9 • 8 7

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followed. Click ‘Continue’ button (refer Fig. 2). 3. Select a chapter of your choice using a pull-down menu (refer Fig. 3). 4. Start attempting the questions (refer Fig. 4). The questions here are generated randomly from the database stored in the server machine. You can select the respective radio button for your choice of answer. 5. As soon as you select an option, click ‘submit’ button to submit the answer and move to the next question. Note that chapters stored in the database can store any number of questions but from those questions, only 15 are displayed on the client side for each test. At the end of 15 questions, a test report is generated (refer Fig. 5), where you can view your performance. To view the correct answers after the test, just click ‘Get Answers’ button on the test report screen (refer Fig. 6).

Testing steps to run the program on a PC Using a single PC, server and client programs can be run at the same time. Here, the server program is under the control of the administrator and the client program is accessed by the student. To achieve this, first the server program is made to run, followed by the client program as explained below: 1. Download ‘Java SE Development Kit (JDK) 6’ from ‘http://java. sun.com/javase/downloads/index. jsp’ website. 2. Install JDK in your machine. By default it is installed under ‘c:\program files\java\jdk1.6.0\bin’ directory. 3. Install MS Access application program and configure the data source for accessing MS Access database from Java as follows: (a) Open ‘Administrative Tools’ from ‘Control Panel.’ (b) Now open ‘Data Sources’ (ODBC) and click ‘Add’ button. (c) Locate ‘Microsoft Access Driver’ (*.mdb) and click ‘Finish.’ 8 8 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

Fig. 5: Test report

(d) Type ‘Data Source Name’ as ‘OnlineExams’ while observing case sensitivity. (e) Assuming that all the relevant programs of this project are stored under ‘D:\Rahul’ folder, locate the database stored in ‘D:\Rahul\’ by using ‘Select’ button of the same window. When the database is selected, you will see the path of your database under ‘Database’ of the same window. (f) Click ‘Ok’ to complete the configurations. 4. Run the server program. All the questions are stored in ‘Questions And Answers’ file of ‘Rahul’ folder. Open the command prompt from ‘Start\Run...’ option and type ‘cmd’ from the keyboard. Open ‘Rahul’ folder from ‘D’ drive. Type the appropriate path against the prompt as given below:

Fig. 6: Solutions to the questions

go to the next step to run the client program. The steps for compiling and running the client program are the same as mentioned above. That is, click ‘Start/ Run’ option followed by ‘cmd.’ Open ‘D:\Rahul’ folder and give the path of the JDK files. 8. Now instead of ‘ServerOnline. java,’ type ‘ClientOnline.java’ against the prompt. If you run the ClientOnline program successfully, you will see the screen as shown in Fig. 1. A PC can handle multiple clients, so you can minimise the current client operation and open another client program on the same machine.

“Path = c:\program files\java\

Testing steps to run on two PCs

This is the path where the JDK files like javac, java and appletviewer are located. 5. Now type command ‘javac ServerOnline.java’ to compile the ServerOnline.java program. If you have set the path correctly, you will find class files under ‘d:\rahul.’ Else, you will find error. Ignore warnings, if any. 6. Next type ‘Java ServerOnline’ on first command prompt to execute the software. You will see “Server Started !!!” in the next line. 7. Minimise the window and then

1. Make sure that the PCs used for the project are connected on a local area network (LAN). 2. Place ‘Rahul’ folder in server and client machines. This is mandatory. Next, follow Steps 1 through 3 under sub-heading “Testing steps to run the program on a single PC.” 3. Provide an appropriate path for JDK as mentioned in Step 4 of the above sub-heading. Compile the ServerOnline.java program and run it on the server machine. 4. On the client PC, the Connect-

jdk1.6.0\bin”

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Software

section

Database1.java file, which is located under ‘Rahul’ folder, requires the IP address of the server. So open the ConnectDatabase1.java source file and replace ‘localhost’ with the IP address of the server wherever ‘localhost’ appears. Save the file and close it. 5. Provide an appropriate path for JDK as mentioned in Step 4 under the previous sub-heading, and compile

both ConnectDatabase1.java and ClientOnline.java programs. 6. Run the ClientOnline.java program. You will see the program output as shown in Fig. 1. Click the appropriate button to proceed for the online exams. EFY-CD. All the relevant files and source codes of this article have been included in this month’s EFY-CD.

serveronline.java BufferedReader is = null; PrintStream os = null; Socket clientSocket = null;

import java.net.*; import java.io.*; import java.sql.*; public class ServerOnline public static void args[]) { try {

{ main(String

String chapterSelected = “”,pass;

DriverManager.registerDriver(new sun.jdbc.odbc.JdbcOdbcDriver()); }catch(Exception e) { System.out.println(“Error occured : “+e.getMessage()); } new ServerClass(); } } class ServerClass ble {

implements

Runna-

Thread t; ServerSocket echoServer = null; Socket clientSocket = null; ServerClass() { try { echoServer = new ServerSocket(1111); }catch(IOException e) { System.out.println(“Could not start server.” + e ); System.exit(1); } t = new Thread(this); System.out.println(“Server started !!!”); t.start(); } public void run() try {

{

while(true) { clientSocket = echoServer.

accept();

connection con = new connec tion(clientSocket); } }catch(IOException e) { System.err.println(“Not listening.” + e); System.exit(1); } } } class connection implements Runnable

{

Thread t; String tableName = “”; //this gets the name of the tablename from where the question and options are to be retrieved String requestQuestion = “”;

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Connection conn; Statement stmt;

public connection(Socket clientSocket) { this.clientSocket = clientSocket; try { is = new BufferedReader(new InputStreamReader(clientSocket.getInputStream())); os = new PrintStream(clientSocket.getOutputStream()); }catch(IOException e) { try { clientSocket.close(); }catch(Exception ex) {} System.err.println(“Unable to setup stream “+e); return; } t = new Thread(this,””); t.start(); } public void run() try

{

{

conn = DriverManager. getConnection(“jdbc:odbc:OnlineExams”); stmt = conn.createStatement(Resu ltSet.TYPE_SCROLL_INSENSITIVE,ResultSet. CONCUR_READ_ONLY); }catch(Exception e) { System.out.println(“Error occured : “+e.getMessage()); } try

{ pass = is.readLine(); if(pass.equals(“1”))

is.readLine(); Selected is.readLine(); lected

{

tableName = //subjecttableName += //classSe-

ResultSet rset = stmt. executeQuery(“Select * from “+tableName); rset.last(); os.println(rset.getString(1)); //lastSNo rset = stmt. executeQuery(“Select * from “+tableNa-

e l e c t ro n i c s f o r yo u • m a r c h 2 0 0 9 • 8 9

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section me);

while(rset.next()) { os.println(rset.get//chapterNos os.println(rset.get//chapterNames }

String(2)); String(3)); }

else if(pass.equals(“2”))

{

is.readLine();

chapterSelected = //chapterSelected

requestQuestion = (String)is.readLine(); ResultSet rset = stmt. executeQuery(“Select * from “+chapterSe-

lected); String(1));

rset.last(); os.println(rset.get-

rset = stmt. executeQuery(“Select * from “+chapterSelected + “ where QNo = “+requestQuestion); if(rset.next()) { os.println(rset.getString(2)); //send question os.println(rset.getString(3)); //send Answer os.println(rset.getString(4)); //send hint }

} }catch(Exception e) { System.out.println(“Error occured while sending/retrieving data: “+e); }finally { try { clientSocket.close(); is.close(); os.close(); stmt.close(); conn.close(); }

}catch(Exception e)

{}

} }

clientonline.java import java.awt.*; import java.awt.event.*; import javax.swing.*; public JFrame

class {

ClientOnline

public ClientOnline() Pane();

extends

{

JTabbedPane jtp = new JTabbed-

jtp.addTab(“Class 10th”,new Class10th()); jtp.addTab(“Class 12th”,new Class12th()); getContentPane().add(jtp); addWindowListener(new WindowAdapter() { public void windowClosing(Wind owEvent we) { dispose(); } }); } public static void main(String args[]) { ClientOnline clonlie = new ClientOnline(); clonlie.setSize(400,150); clonlie.setVisible(true); } } class Class10th extends JPanel implements ActionListener { String subjectSelected = “”; String classSelected = “10”; String[] img = new String[15]; int[] randomQnoStored = new int[15]; public Class10th()

{

JRadioButton physics = new JRadioButton(“Physics”); physics.addActionListener(this); add(physics); JRadioButton chemistry = new JRadi oButton(“Chemistry”); chemistry.addActionListener(this); add(chemistry); JRadioButton biology = new JRadioButton(“Biology”); biology.addActionListener(this); add(biology); JRadioButton mathematics = new JRadioButton(“Mathematics”); mathematics. addActionListener(this); add(mathematics); ButtonGroup

bg

=

new

Button-

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Group(); bg.add(physics); bg.add(chemistry); bg.add(biology); bg.add(mathematics); JButton connect = new JButton(“Connect to DataBase”); connect.addActionListener(this); add(connect); } public void actionPerformed(ActionE vent ae) { if(ae.getActionCommand(). equals(“Connect to DataBase”) && subjectSelected != “”) { try { new ConnectDatabase1(classS elected,subjectSelected,1,1,0,img,img,r andomQnoStored); }catch(Exception e) { System.out.println(“Could not connect to the database Server !!!”+e); } } else if(ae.getActionCommand(). equals(“Physics”)) { subjectSelected = “Physics”; } else if(ae.getActionCommand(). equals(“Chemistry”)) { subjectSelected = “Chemistry”; } else if(ae.getActionCommand(). equals(“Biology”)) { subjectSelected = “Biology”; } else if(ae.getActionCommand(). equals(“Mathematics”)) { subjectSelected = “Mathematics”; } } } class Class12th extends JPanel implements ActionListener { String subjectSelected = “”; String classSelected = “12”; String[] img = new String[15]; int[] randomQnoStored = new int[15]; public Class12th()

{

JRadioButton physics = new JRadioButton(“Physics”); physics.addActionListener(this); add(physics);

JRadioButton chemistry = new JRadi oButton(“Chemistry”); chemistry.addActionListener(this); add(chemistry); JRadioButton biology = new JRadioButton(“Biology”); biology.addActionListener(this); add(biology); JRadioButton mathematics = new JRadioButton(“Mathematics”); mathematics. addActionListener(this); add(mathematics); ButtonGroup bg = Group(); bg.add(physics); bg.add(chemistry); bg.add(biology); bg.add(mathematics);

new

Button-

JButton connect = new JButton(“Connect to DataBase”); connect.addActionListener(this); add(connect); } public void actionPerformed(ActionE vent ae) { if(ae.getActionCommand(). equals(“Connect to DataBase”) && subjectSelected != “”) { try

{ new ConnectDatabase1(classS elected,subjectSelected,1,1,0,img,img,r andomQnoStored); }catch(Exception e) { System.out.println(“Could not connect to database !!!”); } } else if(ae.getActionCommand(). equals(“Physics”)) { subjectSelected = “Physics”; } else if(ae.getActionCommand(). equals(“Chemistry”)) { subjectSelected = “Chemistry”; } else if(ae.getActionCommand(). equals(“Biology”)) { subjectSelected = “Biology”; } else if(ae.getActionCommand(). equals(“Mathematics”)) { subjectSelected = “Mathematics”; } }  }

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Power Supply

Charging Lithium-Ion Batteries Properly restoring energy using the latest battery technology for today’s portable products requires careful consideration. An understanding of the charging characteristics of the battery and the application’s requirements is essential in order to design an appropriate and reliable battery charging system. Linear and switch-mode charging solutions for Li-ion batteries are presented here. Also given are the guidelines and considerations that should be taken into account when developing any battery charging system Each application is unique, but one common theme rings through: maximise battery capacity usage. This theme directly relates to how energy is properly restored to rechargeable batteries. No single method is ideal for all applications. An understanding of the charging characteristics of the battery and the application’s requirements is essential in order to design an appropriate and reliable battery charging system. Each method has its associated advantages and disadvantages. It is the particular application with its individual requirements that determines which method will be the best to use. Far too often, the charging system is given low priority, especially in costsensitive applications. The quality of the charging system, however, plays a key role in the life and reliability of the battery. In this article, the fundamentals of charging Lithium-ion (Li-ion) batteries are explored. In particular, linear charging solutions and a microcontroller-based, switch-mode solution shall be explored.

Li-ion charging



Scott Dearborn

P

owering today’s portable world poses many challenges for system designers. The use of

9 2 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

batteries as a prime power source is on the rise. As a result, a burden has been placed on the system designer to create sophisticated systems utilising the battery’s full potential.

The rate of charge or discharge is often expressed in relation to the capacity of the battery. This rate is known as the C-rate. The C-rate equates to a charge or discharge current and is defined as: I = M × Cn where ‘I’ is charge or discharge current w w w. e f y m ag . co m

Power Supply

Fig. 1: Li-ion charge profile

Fig. 2: Capacity loss vs undercharge voltage

Fig. 3: Typical linear solution

in amperes, ‘M’ is the multiple or fraction of ‘C,’ ‘C’ is the numerical value of 9 4 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

the rated capacity in Ah and ‘n’ is the time in hours at which ‘C’ is declared. A battery discharging at a C-rate of ‘1’ will deliver its nominal rated capacity in one hour. For example, if the rated capacity is 1000 mAh, a discharge rate of 1C corresponds to a discharge current of 1000 mA. A rate of C/10 corresponds to a discharge

current of 100 mA. Typically, manufacturers specify the capacity of a battery at a 5-hour rate, n = 5. For example, the abovementioned battery would provide five hours of operating time when discharged at a constant current of 200 mA. In theory, the battery would provide one hour of operating time when discharged at a constant current of 1000 mA. In practice, however, the operating time will be less than one hour due to inefficiencies in the discharge cycle. So how is energy properly restored to a Li-ion battery? The preferred charge algorithm for Li-ion battery chemistries is a constant-current, constant-voltage algorithm that can be broken up into four stages, namely, trickle charge, constant-current charge, constant-voltage charge and charge termination (refer to Fig. 1): Stage 1 (trickle charge): Trickle charge is employed to restore charge to deeply depleted cells. When the cell voltage is below approximately 3V, the cell is charged with a constant current of 0.1C maximum. Stage 2 (constant-current charge): After the cell voltage has risen above the trickle-charge threshold, the charge current is raised to perform constantcurrent charging. The constant-current charge should be in the 0.2C to 1.0C range. The constant current does not need to be precise and semi-constant current is allowed. Often, in linear chargers, the current is ramped-up as the cell voltage rises in order to minimise heat dissipation in the pass transistor. Charging at constant current rates above 1C does not reduce the overall charge cycle time and should be avoided. When charging at higher currents, the cell voltage rises more rapidly due to over-voltage in the electrode reactions and the increased voltage across the internal resistance of the cell. The constant-current stage becomes shorter, but the overall charge cycle time is not reduced because the percentage of time in the constant voltage stage increases w w w. e f y m ag . co m

Power Supply proportionately. Stage 3 (constant voltage): Constant current charge ends and the constantvoltage stage is invoked when the cell voltage reaches 4.2V. In order to maximise performance, the voltage regulation tolerance should be better than 1 per cent. Stage 4 (charge termination): Unlike nickel-based batteries, it is not recommended to continue to tricklecharge Li-ion batteries. Continuing to trickle charge can cause plating of metallic lithium—a condition that makes the battery unstable. The result can be sudden, automatic and rapid disassembly. Charging is typically terminated by one of two methods: minimum charge current or a timer (or a combination of the two). The minimum current approach monitors the charge current during the constant voltage stage and terminates the charge when the charge current diminishes in the range of 0.02C to 0.07C. The second method determines when the constant voltage stage is invoked. Charging continues for an additional two hours, and then the charge is terminated. Charging in this manner replenishes a deeply depleted battery in roughly 2.5 to 3 hours. Advanced chargers employ additional safety features. For example, the charge is suspended if the cell temperature is outside a specified window, typically 0°C to 45°C.

Li-ion charging: system considerations A high-performance charging system is required to recharge any battery quickly and reliably. The following system parameters should be considered in order to ensure a reliable, costeffective solution. Input source. Many applications use very inexpensive wall cubes for the input supply. The output voltage is highly dependent on the AC input voltage and the load current being drawn from the wall cube. In the US, the AC mains input voltw w w. e f y m ag . co m

Fig. 4: Typical, fully integrated, linear solution

Fig. 5: MCP73843 charge cycle waveforms

age can vary from 90Vrms to 132Vrms for a standard wall outlet. Assuming a nominal input voltage of 120Vrms, the tolerance is +10 per cent, –25 per cent. The charger must provide proper regulation to the battery independent of its input voltage. The input voltage to the charger will scale in accordance to the AC mains voltage and the charge current: VO =√2×VIN×a–1O (REQ+RPTC) – 2×VFD REQ is the resistance of the secondary winding plus the reflected resistance of the primary winding (RP/a2), RPTC is the resistance of the PTC and VFD is the forward drop of the bridge rectifiers. In addition, transformer-core loss will slightly reduce the output voltage. Applications that charge from a car adaptor can experience a similar problem. The output voltage of a car adaptor will be typically in the range

of 9V to 18V. Constant-current charge rate and accuracy. The choice of topology for a given application may be determined by the desired constant current. Many high-constant-current, or multiple-cell, applications rely on a switch-mode charging solution for improved efficiency and less heat generation. Linear solutions are desirable in low to moderate fast-charge-current applications for their superior size and cost considerations. However, a linear solution purposely dissipates excess power in the form of heat. The tolerance on the constantcurrent charge becomes extremely important to a linear system. If the regulation tolerance is loose, pass transistors and other components will need to be oversized adding size and cost. In addition, if the constantcurrent charge is low, the complete e l e c t ro n i c s f o r yo u • M a r c h 2 0 0 9 • 9 5

Fig. 6: Switch mode SEPIC charger

Power Supply

9 6 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

w w w. e f y m ag . co m

Power Supply charge cycle will be extended. Output-voltage regulation accuracy. The output-voltage regulation accuracy is critical in order to obtain the desired goal: maximise the battery capacity usage. A small decrease in output voltage accuracy results in a large decrease in capacity. However, the output voltage cannot be set arbitrarily high because of safety and reliability concerns. Fig. 2 depicts the importance of output-voltage regulation accuracy. Charge termination method. It cannot be stressed enough that over-charging is the Achilles’ heal of Li-ion cells. Accurate charge termination methods are essential for a safe, reliable, charging system. Cell temperature monitoring. The temperature range over which a Li-ion battery should be charged is 0°C to 45°C, typically. Charging the battery at temperatures outside of this range may cause the battery to become hot. During a charge cycle, the pressure inside the battery increases causing the battery to swell. Temperature and pressure are directly related. As the temperature rises, the pressure can become excessive. This can lead to a mechanical breakdown inside the battery or venting. Charging the battery outside of this temperature range may also harm the performance of the battery or reduce the battery’s life expectance. Generally, thermistors are included in Lithium-ion battery packs in order to accurately measure the battery temperature. The charger measures the resistance value of the thermistor between the thermistor terminal and the negative terminal. Charging is inhibited when the resistance, and therefore the temperature, is outside the specified operating range. Battery discharge current or reverse leakage current. In many applications, the charging system remains connected to the battery in the absence of input power. The charging system should minimise the current drain from the battery when input power is not w w w. e f y m ag . co m

present. The maximum current drain should be below a few microamperes and, typically, below one microampere.

Application examples Taking the above system considerations into account, an appropriate charge management system can be developed. Linear solutions. Linear charging solutions are generally employed when a well-regulated input source is available. Linear solutions, in these applications, offer advantages of ease of use, size and cost. Due to the low efficiency of a linear charging solution, the most important factor is the thermal design. The thermal design is a direct function of the input voltage, charge current and thermal impedance between the pass transistor and the ambient cooling air. The worst-case situation is when the device transitions from the trickle charge stage to the constantcurrent stage. In this situation, the pass transistor has to dissipate the maximum power. A trade-off must be made between the charge current, size, cost and thermal requirements of the charging system. Take, for example, an application required to charge a 1000mAh, single Li-Ion cell from a 5V±5% input at a constant-current charge rate of 0.5C or 1C. Fig. 3 depicts a low-cost, standalone linear solution. With a few external components, the preferred charge algorithm is implemented. The MCP73843 combines high-accuracy constant-current, constant-voltage regulation with automatic charge termination. In an effort to further reduce the size, cost and complexity of linear solutions, many of the external components can be integrated into the charge management controller. Advanced packaging and reduced flexibility come along with higher integration. These packages require advanced equipment for manufacturing, and, in many instances, preclude rework. e l e c t ro n i c s f o r yo u • M a r c h 2 0 0 9 • 9 7

Power Supply

Fig. 7: Switch-mode charge cycles with and without PS700, 2200mAh

Typically, integration encompasses charge-current sensing, the pass transistor and reverse-discharge protection. In addition, these charge-management controllers typically employ some type of thermal regulation. Thermal regulation optimises the charge cycle time while maintaining device reliability by limiting the charge current based on the device die temperature. Thermal regulation greatly reduces the thermal design effort. Fig. 4 depicts a fully integrated, linear solution utilising the MCP73861. The MCP73861 incorporates all the features of the MCP73843 along with charge-current sensing, the pass transistor, reverse-discharge protection and cell temperature monitoring. Charge-cycle waveforms. Fig. 5 depicts complete charge cycles utilising the MCP73843 with constant-current charge rates of 1C ad 0.5C. Charging at a rate of 0.5C instead of 1C takes about one hour longer for the end of charge to be reached. The MCP73843 scales the charge termination current proportionately with the fast charge current. The result is an increase of 36 per cent in charge time with the benefit of a 2 per cent gain in capacity and reduced power dissipation. The change in termination current from 0.07C to 0.035C results in an increase in final capacity from around 98 per cent to 100 per cent. The system 9 8 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

designer has to make a trade-off between charge time, power dissipation and available capacity. Switch-mode charging solutions. Switch-mode charging solutions are generally employed in applications that have a wide-ranging input or a high input-to-output voltage differential. In these applications, switch-mode solutions have the advantage of improved efficiency. The disadvantages are system complexity, size and cost. Take, for example, an application required to charge a 2200mAh, single Li-ion cell from a car adaptor at a constant-current charge rate of 0.5C or 1C. It would be extremely difficult to utilise a linear solution in this application due to the thermal issues involved. A linear solution employing thermal regulation could be utilised, but the charge cycle times at the reduced charge currents may be prohibitive. The first step to designing a successful switch-mode charging solution is to choose a topology: buck, boost, buck-boost, flyback, single-ended primary inductive converter (SEPIC) or other. Knowing the input and output requirements, and experience, quickly narrows the choices down to two for this application: buck or SEPIC. A buck converter has the advantage of requiring a single inductor. Disadvantages of this topology include an additional diode required for reverse-discharge

protection, high-side gate drive and current sense, and pulsed input current (EMI concern). The SEPIC topology has advantages that include low-side gate drive and current sense, continuous input current and DC isolation from input to output. The main disadvantage of the SEPIC topology is the use of two inductors and an energy transfer capacitor. Fig. 6 depicts a schematic for a switch-mode charger. A high-speed pulse-width modulator (PWM), MCP1630, has been utilised in a pseudo smart battery charger application. The MCP1630 is a highspeed, microcontroller-adaptable, pulse-width modulator. When used in conjunction with a microcontroller, the MCP1630 will control the power system duty cycle to provide output voltage or current regulation. The microcontroller, PIC16F684, can be used to regulate the output voltage or current, switching frequency and maximum duty cycle. The MCP1630 generates duty cycle, and provides fast over-current protection based on various external inputs. External signals include the input oscillator, the reference voltage, the feedback voltage and the current sense. The output signal is a square-wave pulse. The power train used for the charger is SEPIC. The microcontroller provides an enormous amount of design flexibility. In addition, it can communicate with a battery monitor inside the battery pack to significantly reduce chargecycle times. Charge-cycle waveforms. Fig. 7 shows complete charge cycles utilising the switch-mode charging solution. By utilising a battery monitor in the charging system, charge cycles can be significantly reduced. The battery monitor eliminates sensing the voltage produced across the pack’s protection circuitry and contact resistance by the charging current.  The author is principal applications engineer at Microchip Technology Inc., Chandler, USA w w w. e f y m ag . co m

design Part 1 of 3

Reading the Datasheets of Electronic Devices A thorough understanding of datasheets allows the designers to select the right device for their application and subsequently exploit the potential of the device to the fullest. Beginning this month in a series of three articles, we would focus on how to read a datasheet and then go on to discuss the datasheets of two of the most commonly used electronics devices representing discrete devices and integrated circuits  Anil Kumar Maini and Varsha Agrawal

M

ost of the present-day electronics designers and application engineers do not find it necessary to look beyond the first page of the datasheets of the electronic components or devices while selecting one for their application. They consider the knowledge of a few major specifications of the device sufficient for the design exercise that they wish to undertake. Though it may be adequate in some cases, the design where the components are chosen without giving due consideration to the information contained in the datasheet may not be the optimal one. The datasheet of a device reveals its true character and hence its suitability for a given application. In addition to listing down the device parameters, it gives the electrical and environmental conditions at which these parameters have been measured and also contains information on variation of important parameters as a function of other relevant electrical and environmental parameters. It is vital information particularly when you are designing a circuit or a module that has to qualify stringent environment standards. A comprehensive datasheet almost invariably includes application circuits recommended by the manufacturer.

Comprehensive and condensed datasheets Both comprehensive as well as condensed versions of datasheets are usu-

Fig. 1: First page of datasheet of power Mosfet type IRF250

ally available from manufacturers. The word ‘comprehensive’ is used here to differentiate between the datasheet of a device found in a short-form catalogue and another datasheet of the same device available in the detailed version. For example, a company manufacturing a range of semiconductor devices may have one condensed catalogue containing data on all categories of devices like diodes, bipolar transistors, MOSFETs and thyristors that it manufactures. It may also offer detailed catalogues separately for each of these categories.

1 0 0 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

Surely, the technical data of a given device in the short-form catalogue will not be as comprehensive as it would be in the detailed catalogue. In the condensed version, one is likely to find salient features, major performance specifications, package information and electrical characteristics along with the condition for which they are valid. On the other hand, a detailed datasheet offers a range of characteristic curves showing variation of important parameters as a function of other relevant parameters and typical application circuits. w w w. e f y m ag . co m

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design

Fig. 2: Package styles of op-amp type LM741

Fig. 3: Internal schematic of op-amp type LM741

Common features A study of the datasheets of a variety of devices, be they discrete or integrated circuit (IC), reveals a commonality in the type of data and characteristic curves. These common features are outlined in the following paragraphs. Typical applications and outstand-

ing features. All datasheets begin with typical applications as suggested by the manufacturer and the outstanding features of the device. This information appears on the first page of the datasheet and is an essential part of both condensed and detailed versions. Statements like “It has high dv/dt

1 0 2 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

capability and a low thermal resistance… designed primarily for half-wave AC power control such as motor controls, heating controls… (taken from the datasheet of S2800 series SCR)… high photosensitivity, hermetically sealed… fast optical sensor of high-modulation bandwidth... (taken from the data sheet of PIN photodiode type BPX-65)… single-pulse avalanche energy rated, nanosecond switching speeds, linear transfer characteristics, high input impedance… well suited for applications such as switching regulators, motor drivers, relay drivers… (taken from the datasheet of power MOSFET type IRF250 shown in Fig. 1)” are representative of the first page of the datasheet of the device. This gives designers a fair idea of the important features and applications without going through the whole datasheet. Device package outline. A sketch with device dimensions and lead identification, outline of the package styles of the device and other mechanical information are included in this part. Quite often a given device is made in more than one package style either with no difference in performance specifications (such as medium-power silicon transistor type 2N6045/ MJE6045 made in TO220AB and TO127 package styles), or with a minor difference (such as bipolar transistor 2N2222 in TO-92 plastic and TO-18 metal can packages), and occasionally with a major difference (such as IC regulator type 78-series in TO-92 plastic, TO-220 and TO-3 packages). Fig. 2 shows the package options for the operational amplifier LM741. w w w. e f y m ag . co m

design Absolute Maximum Ratings (Note 1) If military/aerospace specified devices are required, contact the National Semiconductor Sales Office/Distributors for availability and specifications.

LF155/6

LF256/7/LF356B LF355/6/7

Supply voltage

±22V

±22V

±18V

Differential input voltage

±40V

±40V

±30V

Input voltage range (Note 2)

±20V

±20V

±16V

Output short circuit duration

Continuous

Continuous

Continuous

TJMAX

H-package

150°C

115°C

115°C



N-package

—

100°C

100°C



M-package

—

100°C

100°C

Power dissipation at TA=25°C (Notes 1, 8)

H-package (still air)

560 mW

400 mW



H-package (400 LF/min air flow)

1200 mW

1000 mW

400 mW 1000 mW



N-package

—

670 mW

670 mW



M-package

—

380 mW

380 mW

Thermal resistance (typical) θJA

H-package (still air)

160°C/W

160°C/W

160°C/W



H-package (400 LF/min air flow)

65°C/W

65°C/W

65°C/W



N-package

—

130°C/W

130°C/W



M-package

—

195°C/W

195°C/W

(Typical) θJC

H-package

Storage temperature range

23°C/W

23°C/W

23°C/W

–65°C to +150°C

–65°C to +150°C

–65°C to +150°C

300°C

300°C

260°C

260°C

Soldering information (lead temp.)

Metal can package Soldering (10 sec.)

300°C

Dual-in-line package Soldering (10 sec.)

260°C

Small outline package



Vapour phase (60 sec.)

—

215°C

215°C



Infrared (15 sec.)

—

220°C

220°C

See AN-450 ‘Surface Mounting Methods and Their Effect on Product Reliability’ for other methods of soldering surface mount devices. ESD tolerance (100 pF discharged through 1.5kΩ)

1000V

1000V

1000V

Absolute maximum ratings tell the designer the conditions that will damage the device. Remember these are not maximum operating limits Fig. 4: Absolute maximum ratings for op-amp type LF156/256/356

As you can see from the figure, it is available in three packages, namely, the metal can package, dual-in-line package and ceramic flatpak package. Schematic diagram. Detailed schematic of the internal structure of the device is also given in the datasheet. Fig. 3 shows the internal schematic of operational amplifier LM741. It helps the designer to correlate the electrical features of the device with its internal w w w. e f y m ag . co m

architecture. This sometimes helps the designer to explain the device behaviour that is otherwise not described in the datasheet. Absolute maximum ratings. Absolute maximum ratings (Fig. 4) contain information on voltages, currents, powers and temperature range that should never be exceeded. As is evident from the figure, the maximum supply voltage for operational amplifier LF356 is ±18V. e l e c t ro n i c s f o r yo u • M a r c h 2 0 0 9 • 1 0 3

design

Fig. 5: Performance curves of diodes 1N4001 to 1N4007

Performance curves. Performance curves of interest as a function of voltage, current, temperature, etc follow next. These include the

characteristics of the device, such as drain current versus drain voltage (drain characteristics) or drain current versus gate voltage (transfer

1 0 4 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

characteristics) in the case of FETs, emitter voltage versus emitter current in the case of UJTs and forward voltage versus forward current in the w w w. e f y m ag . co m

design case of diodes. Fig. 5 shows the characteristics curves for diodes 1N4001

to 1N4007. It could also be variation of the cathode voltage vs cathode current as a function of temperature (Fig. 6) in the case of a thyristor, or dark current as a function of applied reverse bias in the case of a PIN photodiode, or transconductance versus drain current as a function of temperature in the case of power MOSFET. The curve in the first case emphasises that the relationship between the Fig. 6: Thyristor-cathode voltage vs. cathode current for different temperatures cathode voltage and cath-

ode current changes with temperature. The curve in the second illustration indicates critical dependence of the dark current of the PIN photodiode on the applied reverse bias voltage. And the third demonstrates significant reduction in the transconductance of the MOSFET at a fixed drain current with increase in temperature. These are all very important aspects of design and therefore should not be side-stepped. Electrical characteristics. Electrical characteristics are usually given in tabular form indicating spread in parameter values that is likely to occur in a batch of devices in terms of minimum, typical and maximum values. It is a vital design input as in

Fig. 7: Electrical characteristics of Mosfet type number IRF250

w w w. e f y m ag . co m

e l e c t ro n i c s f o r yo u • M a r c h 2 0 0 9 • 1 0 5

design These are always an asset to the designers, more so for those who are a little short of design experience. Quite often, expressions used to calculate different component values in a given application circuit are also presented. Fig. 8 shows some of the application circuits for operational amplifier LF356 given in its datasheet. The information contained in Fig. 8 is reproduced from the detailed datasheet of LF 355/356/357 series of FET input op-amps.

To sum up... This part of the article highlighted the importance of reading a datasheet and the host of technical information contained therein. In particular, it focused Fig. 8: Some application circuits of op-amp type LF156/256/356 on salient features that are common to the datasheets of all categories of some cases, spread in values could be devices illustrating the significance of as much as an order of magnitude. different parameters with practical exTo substantiate the statement, the amples. The next part of the article will datasheet of C122-series of SCRs from focus on semiconductor diodes. RCA tells that its dv/dt rating could …To be continued be anywhere between 10V/s and 100V/s. Similarly, the gate-source threshold voltage of power MOSFET Anil Kumar Maini is the head of EOCM and Optoelectronics Division and associate director at type IRF250 could vary from 2V to Laser Science and Technology Centre (Defence 4V (Fig. 7). R&D Organisation) and Varsha Agrawal is a senior Application circuits. Application scientist in EOCM and Optoelectronics Division at circuits are usually included only in Laser Science and Technology Centre (Defence the detailed version of the datasheet. R&D Organisation) 1 0 6 • M a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

w w w. e f y m ag . co m

do-it-yourself

A Versatile Frequency Counter Often, the need for a frequency counter is felt that operates in the LF, HF and VHF ranges. The most common deterrents are the lack of programming knowledge and the non-availability of VHF prescalers to bring down VHF to a manageable HF range. Here we show how a commonly available low-cost radio may be ripped apart and used as a frequency counter covering frequencies from 500 kHz to 150 MHz 

Vasuki Prasad

C

hinese radio company Kchibo makes radios based on the CXA1619BM IC. This IC is a surface-mount version of the CXA1619BS, which most designers are familiar with; FM boards available in the market are built using this IC. Kchibo and other companies went a step ahead and thought of implementing a radio frequency display, along with an alarm clock, in their radios so that any station can be tuned into, without doubting the actual frequency which the radio is tuned to (no blind or approximate tuning). This is not a radio synthesiser; it’s a conventional, mechanically tuned radio that sports a frequency display. As opposed to conventional radios which use a single IC (the CXA1619BS/ BM), the so-called digital radio uses two ICs: the radio receiver IC and the UTC6610. At the heart of this project is UTC6610. It comes in many packages, but these radios use the chip-onboard variety. The UTC6610 comes equipped with a frequency counter circuitry, prescaler for VHF, clock circuitry (time), on-chip oscillator, simple adder/subtractor or offset unit, and LCD driver. As can be seen, this unit is completely self-sufficient. The only external components required are crystal and LCD. The frequency counter circuitry of the IC measures the frequency of the incoming RF wave by counting the number of transitions (high-to-low or w w w. e f y m ag . co m

this section. It is used only to keep track of COM1 1 36 VDD time. The on-chip oscilCOM2 2 IN FM 35 lator is a NOT gate COM3 3 34 VSS that requires an exterSEG0 4 33 AMIN nal 32.768kHz crystal SEG1 5 to generate the timing 32 AM/FM-SEL base. SEG2 6 31 RANGE The adder/subtracSEG3 7 30 NC tor unit works like this: SEG4 8 29 IF70K A super heterodyne radio receiver requires SEG5 9 28 AL-OUT a local oscillator operatSEG6 10 27 AL-SIG ing at a fixed frequency SEG7 11 26 CLKFREQ-SEL above the incoming signal’s frequency. This SEG8 12 NC 25 fixed frequency is called SEG9 13 24 HR-SET intermediate frequency, SEG10 14 23 MIN-SET or IF. For commercial SEG11 15 22 AL DISP FM radios, it is 10.7 MHz for FM and 455 SEG12 16 21 AL ON/OFF kHz for AM/SW. OSC IN 17 20 RST Now, if the frequenOSC OUT 18 19 VLCD cy counter was reading the actual frequency of the oscillator, the user Fig. 1: Pin configuration of UTC6610 would have been put to great trouble in determining the actual low-to-high) within a set period. receiving frequency. For example, for a The prescaler for VHF is a divide100MHz signal to be detected, the local by-ten block that probably uses highoscillator is made to run at 110.7 MHz speed CMOS circuitry to divide the (100+10.7=110.7 MHz). So to display number of pulses. When a 150MHz the intended receiving frequency, the signal is fed to the prescalar, the output UTC6610 subtracts 10.7 MHz from the is 15 MHz. Datasheets specify 300mV counted frequency. This means that if peak-to-peak input; higher voltages will you are to use the UTC6610 as a fredestroy the IC. The prescaler is activated quency counter, always bear in mind only in the FM mode of operation. that the actual frequency is 10.7 MHz As regards clock circuitry, we’re higher than the displayed frequency not interested in it and hence skipping

6610

e l e c t ro n i c s f o r yo u • m a r c h 2 0 0 9 • 1 0 7

do-it-yourself Modes of Operation



Function

FM mode details

AM mode details

Input frequency range Prescaler Input voltage Frequency resolution

11 to 150 MHz In operation 300mV pk-pk recommended 10 kHz: 11.00 to 99.99 MHz 100 kHz: 11.0 MHz to 149.9 MHz Set in radio to 100kHz resolution 10.7 MHz 70 kHz also available 150 ohms

0.5 to 30 MHz Not in operation 300mV pk-pk recommended 1 kHz: 500 to 9999 kHz 10 kHz: 0.50 to 29.99 MHz Set in radio to 10kHz resolution for SW and 1kHz resolution for MW 455 kHz

IF offset Input resistance

COL

Fig. 5: The brown PCB with the metallic shield, which is our target

2000 ohms

S1

AM

MHz

FM PM DP2

DP1

KHz AL

(a)

Fig. 6: Opened up: The frequency counter UTC6610 hidden away behind the LCD, while the flip-flop circuitry (just to set FM, AM states) is visible as the SMD transistors Fig. 3: The radio

(b)

Fig. 2: (a) 4 digit-LCD and (b) image of the LCD

in the FM mode. In the AM mode, it is 455 kHz above the displayed frequency. 70kHz offsets are also available as an option in the FM mode, but we are skipping this for now as the radios we rip these modules from have no 70kHz IF. The LCD driver converts binary data into voltages necessary to drive the LCD unit.

Fig. 7: The back side: RF shield-cum-LCD mechanical support. Notice the purple and black wire for VHF and HF input, respectively

Opening up the radio The best part about Kchibo KK-939B radio is use of minimal external points. Also, it is simple to understand and operate, has an LED light to illuminate the LCD, and looks good. I recommend beginners to buy this radio and rip it apart for a clean, high-performance frequency counter. To access the frequency counter board, the radio (Kchibo KK-939B) has to be opened up. In the close-up of the

Fig. 4: Opened up radio; note that the brown PCB is the frequency counter and LCD section and green PCB is the radio receiver

frequency counter PCB (Fig. 9), you will notice the solder joints marked VH input, HF input, points ‘1’ through ‘5,’ FM and AM. VHF input is to be connected to the RF source whose frequency you want to determine (from 11 to 150 MHz). HF input is to be connected to the RF source whose frequency you

1 0 8 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

Fig. 8: The purple line leads to the take-off point for the VHF oscillator (FM section), while the rightmost black wire leads to the take-off point for the AM oscillator

want to determine (up to 30 MHz). ‘1’ is an input point. It has to be kept at 0V for FM (VHF) operation and 10kHz resolution in the AM mode w w w. e f y m ag . co m

do-it-yourself PCB provided by the manufacturer of the radio, so as to come up with a quick, compact, cost-effective RF counter. To have a look at the IC, lift the LCD, and you will see that the chipon-board (COB) is the UTC 6610 (see Fig. 10).

Making the RF counter Fig. 12: Crude connection example

Fig. 9: Close-up of the frequency counter PCB

Fig. 10: The chip-on-board is the UTC6610

(HF operation). Setting it to Vcc in HF mode only sets the display resolution to 1 kHz. ‘2’ is an output point Fig. 11: Connect a small for the radio switch between point ‘1’ and GND and Vcc which lets the IC know whether it’s the AM (SW/MW) mode or FM mode. ‘3’ is an input point at Vcc (3V, do not exceed 3.3V). ‘4’ is the input point at GND. ‘5’ is the output point that controls power to the radio, shutting off power to the IC when in clock mode. Pressing FM button activates the VHF counter with a resolution of 100 kHz and frequency range of 11 MHz to 150 MHz. The input is via the purple wire (shown in Fig. 9); the colour may differ in your radio. You must set point 1 to 0V for proper operation. The display reading must be added to 10.7 MHz to get the actual frequency. w w w. e f y m ag . co m

A flip-flop comprising SMD transistors on the PCB locks the UTC in this mode until the AM button is pressed. Default mode on startup is the FM mode. Pressing AM button activates the HF counter with frequency range of 0.5 to 30 MHz. The input is via the black wire (shown in Fig. 9); the colour may differ in your radio. Set point 1 to Vcc for 1kHz resolution and RF input of 0.5 to 9.999 MHz. Set point 1 to 0V for 10kHz resolution and 0.5 MHz to 29.99 MHz. Actual tests show it exceeds 75 MHz in this mode, which is good. Reading on the display must be added to 455 kHz to get the actual frequency. A flip-flop comprising SMD transistors on the PCB locks the UTC in this mode until the FM button is pressed. Default mode on startup is the FM mode. To activate the AM mode, this button has to be pressed. Notice the blob of solder above the VHF input point. This is the ground. Of course, the clock pushbuttons are still working perfectly, so you may use them to set the clock too. You will have to shift the SPDT switch (the switch which controls the radio ‘on’ and ‘off’) to ‘off’ position in order to activate the clock, and to ‘on’ position in order to activate the RF counter. Please note that here we’re not trying to use the UTC6610 directly. Most of the hard work of wiring up the 6610 IC, providing an LCD, making the PCB and adding components has been done by the radio manufacturer; in this case, Kchibo. All we are attempting to do here is to understand operation of the UTC6610, and in turn operation of the

1. Cut out the 5-wire ribbon cable. Unsolder it from the counter board. 2. Cut the VHF and HF input wires from the points on the radio PCB, not the counter PCB. 3. The counter PCB is now separated from the radio receiver PCB. 4. Solder a red wire to point ‘3’ of the counter PCB. This is your positive 3V supply wire. 5. Solder a green wire to point ‘4’ of the PCB. This serves as ground. 6. Connect a small switch between point ‘1’ and GND and Vcc, as shown in Fig. 11. Push the switch to 1kHz position for 1kHz resolution in the AM mode, and to 10kHz resolution for 10kHz in the AM mode. The switch has to be kept in the 10kHz resolution mode for proper VHF operation (FM mode). With this, your crude-looking but great-performance RF counter is set to go. But bear a few things in mind: 1. Keep the VHF and HF wires as short as possible. Their length will not affect the performance of the counter, but the circuit under test (for example, the oscillator you might have built). 2. Couple the HF and VHF wires to the RF sources via a 2pF capacitor. 3. Preferably, replace the VHF and HF crude wires with easily available 75-ohm cable TV coax. This provides RF shielding and noise immunity to a good degree. Fig. 12 shows a crude connection example. Note how the green wire (HF wire) is directly fed to the output of the oscillator (very crude, do not attempt this), without any capacitor or buffer. (I admit this green wire belongs to a different counter, but the operation and concept are the same, as it too uses the UTC6610.) Once I disconnected the counter from the oscillator I had made,

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do-it-yourself the frequency moved up by 1 MHz. What is important to understand here is: If you’re keeping the counter connected to the output of a nonbuffered oscillator, the reading of the counter plus 455/10.7 (as the case may be, FM or AM mode, as shown on the LCD) will be the true reading. Attempting to count the frequency and then disconnecting the counter will set the oscillator at a different frequency after counting due to the capacitance and loading effect of the counter. The reading got then is invalid as the frequency changes on the removal of the counter. Keeping this effect in mind, it is important to: 1. Use the 2pF capacitor. It causes minimal frequency shift due to minimal capacitance effect, so that the reading obtained, and the frequency after removing the counter from your oscillator, don’t differ much. 2. Buffer your oscillator. Buffering of oscillators is very important to prevent your oscillators from being affected by external components.

Fig. 13: Suggested connection

Fig. 13 shows the suggested connection. Never connect the HF and VHF counter pins together. Use separate ports and coax cables for both.

Why it’s good for beginners? There are other radio receiver models available with more work to do (in terms of points). Fig. 14 shows an example: As you can see, the number of lines is more, and more connections have to be made in order to get it working. But for a beginner, the KK939B is a great radio with a great counter board. It has on-board flip-flops that make the external connections simple. In the case of the board shown in Fig. 14, all the flip-flops are on the radio PCB, so the number of connec-

Fig. 14: Another radio receiver example

tions is much more. Besides, separating the counter PCB from the radio PCB removes the luxury of pushbuttons and flip-flops; which are present in the KK-939B. It took me two month to understand the operation of the counter shown in Fig. 14. After all the UTC6610 learning and circuit decoding (extensive), the KK-939 took only 17 minutes flat. That’s why it’s good for beginners. Enjoy and have fun with your inexpensive counter. The radio should be available for Rs 250 or less. Have fun!  The author is from Manipal Institute of Technology

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wireless

Bluetooth Scatternets A Cost-Effective Solution for Communication The most popular application of Bluetooth is communication between two directly paired devices. Here, we explore a less popular but powerful application of Bluetooth which can help extend the range of Bluetooth communication and provide a free infrastructure for communication Scatternets: A set of piconets

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Ahzam Ali

B

luetooth is a low-power, lowcost and short-range wireless technology. It was originally developed by Ericsson for short-range communication between personal devices, e.g., data transfer between a cellphone and a computer, or communication with a printer. Bluetooth devices use the unlicensed ISM band at 2.4 GHz. Nowadays most of the mobile devices, including mobile phones, MP3 players, digital cameras, video cameras, PDAs, laptop PCs, tablet PCs and so forth, are equipped with Bluetooth. So you can exchange data between these devices without requiring the use of wires. Bluetooth is considered to be a high-potential technology for providing wireless communication in a home-networking environment.

Bluetooth is an evolving technology. It has gone through three (standardised) revisions of the approved standard by Bluetooth Special Interest Group (SIG), the latest one being Bluetooth 2.1 EDR (enhanced data rate) in early part of 2008. The latest standard supports enhanced usability, i.e., pairing of devices by means of near-field communication (NFC), enhanced security and broader range of device profiles. When a number of Bluetooth devices communicate to each other in the same vicinity, there is a high level of interference. To combat interference, Bluetooth technology applies a fast frequency-hopping scheme which hops over 79 channels 1600 times per second. For devices to communicate to each other using Bluetooth they need to be paired with each other to have synchronised frequency-hopping sequence.

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When there is a collection of devices paired with each other, it forms a small personal area network called ‘piconet.’ A piconet consists of a master and at most seven active slaves. Each piconet has its own hopping sequence and the master and all slaves share the same channel. In a piconet, the master and slave devices transmit packets in even and odd slots, respectively. Two or more piconets connected to each other by means of a device (called ‘bridge’) participating in both the piconets, form a scatternet. The role of the bridge is to transmit data across piconets. Fig. 1 shows a scatternet structure in which devices ‘a’ and ‘c’ play the master role and device ‘b’ acts as the bridge. The scatternet formation has not been formally defined in the Bluetooth SIG specifications. As a result, numerous protocols have been proposed. While modeling ad-hoc networking, in general, is complex, the additional restrictions imposed by the Bluetooth specifications—such as low cost of the device, low power consumption and network resilience while using piconets that have a maximum of seven active nodes—have created a c

P1 a

b

P2 MASTER SLAVE BRIDGE

Fig. 1: Scatternet structure

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wireless significant challenge.

Formation of scatternets There has been a comprehensive study to propose an efficient formation of connected scatternet. One important problem that exists with scatternet as well as piconet formation is to keep track of the device that comes in and goes out of the network—since these are low-power handheld devices with limited communication range over Bluetooth. A device connects to another device at random, according to their 48-bit Bluetooth addresses and clocks, which control the hopping behaviour in inquiry or inquiry scan states. Most protocols seek to reduce the scatternet formation time and form fast routing algorithms. It turns out that a good scatternet formation protocol should: 1. Be fully distributed and rely on local information 2. Generate connected scatternets 3. Be resilient to the disconnection of nodes anywhere in the scatternet 4. Provide multiple routes for robustness and be self-healing 5. Limit the number of bridges 6. Limit the number of roles a device can assume 7. Be aware of device resources While forming a scatternet, keep in mind that you are dealing with, in general, small, energy- and processing-power-starved devices. The following points should be taken care of while developing scatternet formation protocols: 1. Minimise scatternet construction time 2. Minimise the amount of control data transmitted 3. Minimise the number of hops required for communication between devices, in order to improve response times 4. Minimise power consumption. Master-and-bridge mode of operation requires more power than slave mode 5. Minimise the number of roles assigned to nodes 6. Minimise the number of piconets to provide faster routing and reduced w w w. e f y m ag . co m

Fig. 2: Showing efficient network after role switching

Fig. 3: Unnecessary bridge elimination

packet collisions 7. Maximise the amount of data throughput Given a scatternet, you can evaluate its performance based on the number of piconets, the number of nodes per piconet, the number of bridge nodes, the number of roles per node, average traffic delay, throughput and maximum traffic delay. Numerous models have been proposed for constructing Bluetooth scatternets, some of which may require modifications to the existing Bluetooth specifications.

Role switching Role switching enables two devices to exchange roles very rapidly, rather than reconnecting by executing the time-consuming inquiry and inquiry scan processes. The role switching operation involves fewer slots than the inquiry/inquiry scan and page/page scan operations in switching the roles of the devices. There are three major types of role switching operations: 1. Combining. A situation where a single node works both as slave in one piconet and master in another. 2. Splitting. A piconet with a large number of devices divided in two piconets with smaller number of devices. 3. Take-over. When the existing mast or a bridge is about to move out

of the scatternet, it transfers its responsibilities to another device in the scatternet. There is a switching delay (called ‘guard time’) introduced by bridges while they try to transmit packets across the piconets. Eliminating the unnecessary bridges from the network will improve the performance of the scatternet. There exist various protocols and algorithms to optimise the roles that a device assumes in a scatternet. We see in the following examples how effective role assignment can reduce the hop count while routing a packet, help reduce the number of bridges in the network and result in an efficient scatternet structure. In Fig. 2, the original network was formed with ‘c’ as a bridge node and ‘a’ and ‘b’ as the masters on two different piconets p1 and p2. Using role switching, with the help of ‘c,’ improves the structure of the scatternet (now formed as a ‘piconet’), shortens the routing path and eliminates the bridge delay in the network. Fig. 3 shows another example of better role switching operation that results in an improved network structure.

Scatternet applications By now you might be wondering what possible use these scatternets could be put to. Well, there are papers proposing voice communication between two mobile devices connected over a Bluetooth scatternet, up to a distance of 100 metres in an indoor environment. One of the popular applications developed by Nokia, called ‘sensor,’ works on somewhat similar principles. It lets users communicate to each other, bypassing the service provider’s network, over Bluetooth. Sensor networks are another example where the Bluetooth scatternets can be used. Since sensor networks are generally ad-hoc, Bluetooth scatternet can be used for communication of sensors with each other and the base. This will eliminate the requirement of

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wireless developing a special-purpose protocol for sensor networks.

Problems to be addressed The Bluetooth scatternet formation devices are generally small, running on batteries, with low-powered CPU and low memory. At the same time, these are highly mobile and may frequently move in and out of the network. This leads us to think about: 1. Topology and size of scatternets. What is the optimal number of piconets in the scatternet and how many nodes are there? The number of bridge nodes increases (proportionally) with the increasing number of piconets. The increases, in turn, incur significant overhead: loss of one or more time slots to readjust clocking when shifting from one piconet to another, more traffic than non-bridge nodes and increased battery power consumption to perform these tasks. What is the optimal number of piconets in which a bridge should participate? The more the piconets with which a bridge communicates, the less the time during which the bridge will be available for dealing with traffic from/to each individual piconet, thus increasing the likelihood of bottlenecks, at the bridge itself. 2. Formation delay and resilience. How much time is required to construct, optimise and maintain the scatternet? The ad-hoc, dynamic nature of a Bluetooth network requires constant modifications to the scatternet topology to support devices that join and leave. How to handle the nodes that join or leave the scatternets? 3. Polling and scheduling. In what order will the slaves be polled by the master? Does the scatternet topology impact the ability to handle scheduled communications from slaves in sniff or hold state? 4. Routing. Does the scatternet topology allow efficient routing of messages?

Work in the area There are a number of papers discussing the effective routing protocols

for Bluetooth scatternets. Also, there are quite a few papers which discuss the point of organising the scatternet in an efficient fashion, dealing with disparate aspects of scatternet optimisation. A proposal in ‘Bluetooth Scatternet Formation for Supporting Device Mobility,’ by Chorng-Horng Yang and Yi- Sheng Chen, deals with mobility support in a Bluetooth scatternet network, but relies on a Bluetooth backbone network consisting of devices that are not mobile. Another work done on similar lines is ‘Tracking the Optimal Configuration of a Bluetooth Scatternet’ by Csaba Kiss Kalló and Carla-Fabiana Chiasserini, which deals with similar problem of redefining the role of nodes in scatternets but concentrates on improving the energy efficiency of the nodes. Also, there are numerous proposals for routing protocols including MANET (mobile ad-hoc network) protocols.

Future in Bluetooth The new Bluetooth specification, called the Bluetooth 2.1, is already published. It is fully backward-compatible with 1.1. The specification includes many new security and usability enhancements. The most interesting of these is incorporation of the near-field communication (NFC) device, which helps in pairing of two Bluetooth devices equipped with NFC chip by just bringing them close to each other. For example, a headset can be paired with a Bluetooth 2.1 phone having NFC chip just by bringing the two devices close to each other. Another example is automatic uploading of photos from a mobile phone to a digital picture frame just by bringing the phone close to the frame. Features like this and other security enhancements will help Bluetooth gain user confidence. A lot of work is in progress in the area of Bluetooth, to enhance and widen the application of Bluetooth protocol. In the future, we may expect features like: 1. Broadcast channels. These will enable Bluetooth information points

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that broadcast information to all Bluetooth devices in the vicinity. So users will be able to pull relevant information from the system. 2. Topology manger. It will enable better configuration of piconets and even scatternets. 3. Alternate media access physical layer. It will enable use of some other wireless technology for actual data transfer at higher rate while maintaining the initial pairing on standard Bluetooth. 4. QoS improvements. These will enable audio and video data transmission at a higher quality. Nokia and Bluetooth SIG have announced that Wibree (Nokia’s low power wireless communication protocol) will be a part of the Bluetooth specification as an ultra-low-power Bluetooth technology, to be used in caller ID watches, sports sensors (used for monitoring the wearer’s heart rate during exercise) as well as medical devices. A medical devices profile and associated protocols are being developed by the Medical Devices Working Group (MDWG). Bluetooth 3.0. The next version of Bluetooth after v2.1, code-named Seattle, is proposed to adopt ultra-wideband (UWB) radio technology. This will allow Bluetooth use over UWB radio, enabling very fast data transfers of up to 480 Mbps, while taking the advantage of very low-power idle modes of Bluetooth.

Extending the scope Even though work on Bluetooth scatternet is going on for about a decade now, it has failed to generate interest amongst general consumer electronics goods manufacturers. Bluetooth scatternets find most of their use in sensor networks. When there is a limitation on setting up the communication infrastructure, Bluetooth scatternet could turn out to be a cost-effective solution. In future, as the processing power of electronic devices grows and they become more energy-efficient, Bluetooth might see its way into already evolving Bluetooth standards.  w w w. e f y m ag . co m

Recently introduced in India, From near and far

New Products Storage Stylish hard drive

Transcend Information, Inc. has announced a 6.4cm (2.5-inch) portable hard drive. The elegant and sleek StoreJet 25F measures only 113.8×80.9×15.9 mm3. It is designed for business travel-

levels of system performance, capacity, reliability and lower power consumption. Built for 8.9cm Tier 1 storage applications, the 15K.7 and the NS.2 are said to be the largest-capacity, mission-critical drives offered at 600 GB. The 15K.7 is claimed to deliver the highest performance of any 8.9cm drive, while the NS.2 features the lowest power requirement of any 8.9cm Tier 1 drive. Fortune Marketing (Seagate Distributor), New Delhi Phone: (011) 26414468, 26472491 E-mail: [email protected]

ers and people who prefer an elegant way to carry their data. Despite its compact size, the StoreJet 25F has up to 500 GB of storage space, so you can easily transfer, store and share important files and data. Supertron Electronics Limited, Kolkata Phone: (033) 22131221-23 E-mail: [email protected]

Enterprise-class hard drives

Seagate has announced two new members of its Cheetah enterprise-class hard drive family: the 15K.7 and the NS.2. For businesses that have an existing investment based on a standard 8.9cm (3.5-inch) enterprise infrastructure, the new Cheetah drives bolster sustainability through easy drive/system integration, and provide improved

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Test & measurement Reference thermometers

Hart Scientific, a division of Fluke Corporation, has introduced the Fluke 1523 and Fluke 1524 handheld reference thermometers for platinum resistance thermometer (PRT), thermocouple and thermistor temperature measurement. The single- and dual-channel models feature precision components and circuitry to put lab-quality measurement in easy reach of field technicians and engineers. These rugged and affordable thermometers offer accuracy of ±0.002°C— a level appropriate for high-precision field work in oil, gas and other industries, where the current practice is the use of toxic mercury-in-glass thermometers. Fluke guarantees the specifications in –10°C to 60°C

ambient temperatures, with the best performance over the range of 13°C to 33°C. TTL Technologies Pvt Ltd, Bangalore Fax: (080) 25291285 Phone: 25260646, 25251859 E-mail: [email protected] Website: ttlindia.com

Handheld digital multimeters

Messals Overseas (India) has introduced high-performance, handheld digital multimeters (model Nos 1061 and 1062) from Kyoritsu, Japan. These 50,000-count, true-RMS multimeters have basic DC accuracy of 0.025 per cent. They use high-performance, UL-standard fuses with user calibration function. Peak-hold response time is 250 µs. The multimeters can measure AC/DC voltage up to 1000V, current up to 10A and resistance up to 50 mega-ohms. Other functions include temperature and capacitance measurements with diode test and continuity check. Messals Overseas (I) Pvt Ltd, Jaipur Fax: (0141) 2706639 Phone: 2705361 E-mail: [email protected]

Tools & Equipment Energy saver

The Coolite energy saver by Conzerv helps to save 10 to 20 per cent of direct lighting energy consumption and runs lamps cooler. It looks similar to a computer’s CPU and has to be connected to the lighting supply. Coolite is suitable for stabilised lighting circuits in commercial buildings and complexes, hotels, hospitals, BPOs, cinema halls, auditoria, stadia

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(indoor/outdoor), educational institutions, residential buildings and apartments and all industrial facilities. It filters harmonics injected to the line by electronic lighting ballasts and reduces spikes in lighting circuits.

operation of logic signals, coil-winding machines, photo lab equipment, sewing machines, packaging equipment, conveyor belts, printing equipment and CNC machines.

E Power Engineering, Chennai Fax: (044) 24337599 Phone: 24337598

Teknic Electromeconics Pvt Ltd, Bangalore Fax: (080) 28520254 Phone: 28520389, 28520714 E-mail: [email protected]

Inductive proximity sensor

Air-dust cleaner

R.S. Electronics has introduced inductive proximity sensors that can detect the presence of a wide range of metallic targets. This detection is accomplished without contacting the target and is mechanically wear-free. The sensors are available in DC as well as AC, in various sizes ranging from M8 to M80, with various

configurations and sensing distances. Inductive micro box sensors, slot sensors or any other type of sensor can be supplied as per the specific requirement. R.S. Electronics, Chennai E-mail: [email protected]

Cecon Pollutech Systems has introduced a high-efficiency, portable, air-dust cleaner designed to create dust-free atmosphere in conditioned and non-conditioned areas. Cleaning efficiency of this system is 0.1 micron with power consumption of 150 watts. The wall-hanging cleaner is easy to install with low maintenance cost and nil consumables required for operation. It is highly useful for places like currency chest and sorting areas in process control rooms of banks, telephone exchanges, research laboratories, operation theatres, and other places requiring clean and dust-free atmosphere. Cecon Pollutech Systems (P) Ltd, Lucknow Telefax: (0522) 2386331 Phone: 2700202, 2391709 E-mail: [email protected]

Networking

Foot switch

Teknic’s foot switch (type FS-99) is ideal for any light- to medium-duty application, with an electrical rating of 16A, ½HP, 250V AC. It can serve as a foot-operated, ‘on’/‘off’ switch for a wide range of motor-driven and electrical devices. The switch is constructed with a sturdy metal housing and can be used as an independent product, but can also be supplied with an additional guard in different colours for certain applications. The switch can be used in

Broadband router

Edimax’s Ultra Range plus Wireless-N broadband router is a 3-in-1 device. First, there’s the wireless access point, which lets you connect to the network without wires. There’s also a built-in 4port, full-duplex 10/100 switch to connect your wired-Ethernet devices together. Finally, the router function ties it all together and lets your whole network share a high-speed cable or DSL Internet connection.

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Edimax Technology Co. Ltd, New Delhi Phone: (011) 41608180 E-mail: [email protected] Web: www.edimax.com

Components IGBT for xenon flash

Sanyo Semiconductor claims to have developed the industry’s smallest IGBT for xenon flash to be used in portable camera phones and compact

digital cameras. The new IGBT reduces its mounting area by 60 per cent compared to Sanyo’s current products while keeping the equivalent performance required for light control of the xenon flash. This new product is ideal for portable camera cell phones as well as compact digital cameras. The IGBT contributes to environmental friendliness by incorporating lead-free external terminals, halogenfree packaging and reduction of rare metals used. Smaller, thinner, and high-performance package leads to resource savings and energy efficiency. Sanyo Semiconductor (S) Pte Ltd, India Liaison Office, Noida Fax: (0120) 4232108 Phone: 4232106-8, 4232109 (Direct) E-mail: [email protected]

Broadband signal amplifier IC

STMicroelectronics has introduced a broadband signal amplifier IC that supports higher frequencies and faster response, as well as lower noise, than amplifiers used in current equipment. The TS617 supports up to 200MHz operation, which will satisfy faster broadband services such as 24Mbps ADSL2+, and VDSL offering up to 100Mbps download and upload speeds. It is also optimised for use in broadband powerline networking w w w. e f y m ag . co m

using standards such as HomePlug 1.0 and HomePlugAV. HomePlugAV is a new standard developed by the HomePlug Powerline Alliance which will allow home entertainment devices to share the Internet and TV, audio and video using AC mains wiring instead of dedicated network cables. STMicroelectronics Marketing Pvt Ltd, Noida, Uttar Pradesh Fax: 0120-4243417 Phone: 4243400

Miscellaneous TFT monitor

Moser Baer India has launched a sleek and stylish LCD TFT monitor for those who have a knack for gaming, video

editing and other multimedia applications. The monitor (MBI TFTL5C) is priced at Rs 7000, thus making it ideal for low-cost entertainment and gaming. Its other features are 38cm (15-inch) wide display with high resolution, fast response time of six microseconds and aspect ratio of 16:10. Moser Baer India Ltd, New Delhi Phone: 26911570-74 Fax: (011) 26911860 E-mail: [email protected]

SDHC video cards

Kingston Technology Company, Inc., has released a line of SDHC video cards for use in digital camcorders. The SDHC video cards carry plenty of recording time and are available in 60minute (4GB), 120-minute (8GB) and 240-minute (16GB) capacities. The cards feature a Class-4 speed rating, which guarantees a minimum data transfer rate of 4 MB/s, making them ideal for use in the latest digital w w w. e f y m ag . co m

camcorders and for fast transfer from the card to a PC. Kingston Technology, Mumbai Phone: (022) 26592961 E-mail: [email protected] Website: kingston.com/asia

Video encoder

Axis Communications has introduced a highly compact and cost-effective one-channel video encoder with H.264 video compression. The M7001 video encoder is perfect for integrating small or large numbers of analogue CCTV surveillance cameras into an IP-based video surveillance system. Installed close to an analogue camera, it converts analogue video signals from the analogue camera into digital video streams that are then sent

over an IP-based network (LAN/intranet/Internet). The video encoder also provides pan, tilt and zoom support to PTZ and PTZ dome cameras. AXIS M7001 can deliver two simultaneous video streams, one in H.264 and another in Motion JPEG, at full frame rate in all resolutions up to D1 (720x480 in NTSC, 720x576 in PAL). It drastically reduces bandwidth and storage requirements without compromising image quality. Axis Video Systems India Private Limited, Bangalore Fax: (080) 40239111 Phone: 41571222 E-mail: [email protected] e l e c t ro n i c s f o r yo u • M a r c h 2 0 0 9 • 1 1 7

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corporate news

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new ventures

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calendar

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new appointments

Industry News In Focus

Semiconductor market continues to grow

Satoru Ito to retire as Renesas chairman, CEO

The total revenues of the Indian semiconductor market are poised to grow from $5.9 billion in 2008 to $7.59 billion in 2010 at a CAGR of 13.4 per cent. The total available market revenues are anticipated to climb from $2.53 billion in 2008 to $3.24 billion in 2010 with a CAGR of 13.1 per cent, according to a report by The India Semiconductor Association (ISA) and Frost and Sullivan (F&S). IT and office automation, wireless handsets and communication segments are going to define the semiconductor market growth. The semiconductor market growth is expected to be driven by such products and services as set-top boxes, wireless handsets, the 3G rollout, deployment of WiMAX, notebooks and smart cards. Opportunities exist for semiconductors in LCD TV, digital camera and storage Flash memory markets.

Telecom too shows growth Defying the economic slowdown, the telecom sector has witnessed a robust growth. The companies are adding substantial number of subscribers and this trend is persisting for the last many quarters. For instance, the aggregate net subscriber addition during the quarter ended December 2008 was around 31.6 million resulting in a sequential growth of 10 per cent. Indian telecom services providers are at different phases of their growth cycles and have adopted different business models to attract new customers. Bharti Airtel, which is the market leader with around 25 per cent market share, is in a stable growth phase, thanks to its pan-India GSM service. The other two big players—Reliance Communications (RCom) and Idea—are launching their GSM serv-

Renesas Technology has announced changes in its management team, with effect from April 1, 2009. The new appointments are subject to approval of the general shareholders’ meeting to be held before the end of March 2009. Satoru Ito, chairman and CEO since April 2006, will retire from his position. Katsuhiro Tsukamoto, currently president and COO, will be appointed as the company’s chairman and board director. And, Yasushi Akao will take up the post of president, while continuing as board director.

NDS India, a provider of technology solutions for digital pay-TV, has appointed Alan Dishington as the director of sales. Based out of New Delhi, Dishington will be reporting to Sue Taylor, senior vice president and general manager, NDS Asia Pacific. In his new position, he will oversee all Indian business development, sales and pre-sales activities. He will be responsible for identifying and developing new business opportunities for NDS end-to-end payTV solutions in India in cable, satellite (DTH) and IPTV.

Samsung appoints GM-IT volume sales

Rathore is Videocon’s chief marketing officer

Samsung India has appointed Gurpreet Brar as the general manager for its IT volume sales business. In this role, Brar will handle the company’s volume business, comprising LCD monitor, HDD, OMS and notebook PC product categories along with the company’s retail business for both the volume and printer business in India.

Jaideep Rathore has been appointed as the chief marketing officer by consumer durable firm Videocon. Earlier, Rathore was heading the company’s Italy operations. Rathore would be overseeing the marketing functions of all the brands for consumer electronics and appliances of Videocon across the country.

ices in different circles of the country. From aggressive marketing to very low tariffs, these two companies are adopting every startegy to attract subscribers in the circles they have launched their services recently. Almost all companies are increasing their network capacity, setting up new equipment for technology adoption or spending more money to acquire new subscribers.

Flat growth expected in PC sales Given the current macro-economic conditions and conservative buying sentiment in the market, the overall PC sales in fiscal 2008-09 are expected to remain at the same levels as in the last fiscal at 7.3 million units. As per the findings of The Manufacturers’ Association for Information

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NDS appoints director-sales

Technology (MAIT), the total PC sales between April and September 2008, with desktop computers and notebooks taken together, were 3.69 million units, registering a growth of 12 per cent over the same period last fiscal. The sales of desktops stood at 2.91 million units, registering a growth of 12 per cent. Notebooks recorded a consumption of 770,000 units, growing 13 per cent over the same period last year. The desktop PC and notebook sales in fiscal 2008-09 are expected to be 5.5 million units and 1.85 million units— almost the same as in fiscal 2007-08.

HDTV broadcast to start soon in India Doordarshan plans to broadcast next year’s Commonwealth Games in highdefinition TV (HDTV) format. HDTV w w w. e f y m ag . co m

will provide viewers a picture that is 16 times better than regular television. The Information and Broadcasting Ministry has asked for the Cabinet’s approval for studios in four metros to broadcast the games on HDTV, already adopted by BBC and Sky Sports. However, to get HDTV broadcast, the end user’s TV should be HD-enabled. For that you can buy an HD-compatible TV or a set-to box to make your existing TV HD-compatible.

Delhi to get its SEZ The Delhi government plans to establish a special economic zone (SEZ) in the capital. The government has also identified sectors for the setting up of SEZs, which include electronic hardware and software, information technologyenabled services (ITeS), nanotechnology and biotechnology amongst others. No polluting industries will be allowed to set up inside SEZs, and environmental clearance is a must for all projects except those dealing with ITeS. The proposed SEZ should also conform to the land use pattern prescribed in the overall Master Plan Delhi 2021, and only those proposals where the applicants already have adequate land as prescribed under the SEZ Act will be considered by the government.

Videocon forays into power backup business Consumer durable major Videocon has entered the power backup equipment space with the launch of a range of devices. With this new venture, the company aims to reach a revenue of Rs 5 billion by next year and further it to Rs 10 billion by 2011. The products will be available in three variants (600VA, 800VA and 1400VA), in the price range of Rs 4990 to Rs 11,990. The company has also introduced batteries in the market.

Samsung to launch nine digicams Samsung India is betting big on the digital camera market and plans to launch nine new models in the first half of 2009. w w w. e f y m ag . co m

“This year, we expect the 7- and 8-megapixel resolution cameras to continue to dominate the market. We also expect to see the introduction of full high-definition digital cameras in the Indian market,” shared R. Zutshi, deputy managing director, Samsung India. Samsung closed 2008 with a market share of around 11 per cent in the digital still camera market. It is now looking at doubling its volumes this year based on the introduction of nine new digital still camera models in the first half of this year.

ViewSonic remodeling its distribution plans ViewSonic has announced its expansion plan for India for the year 2009. The company is planning to introduce in India its high-end products such as all-in-one PCs and netbooks. To unveil these products, ViewSonic is remodelling its distribution plans for India. Alan Chang, managing director of ViewSonic International, said, “Our focus now is to scale up the Indian operations by launching unique concept product lines suited specifically to the Indian environment of operation that not only provide innovative solutions to the customers but also set a benchmark for the industry to follow.” In addition, the company would be launching a demo drive through its key channel partners in the metro cities. This would be later followed by a country-wide aggressive marketing initiative to educate the customers on the benefits of these concept products.

Dixon to set up LCD TV unit Dixon Technologies, the owner of the consumer durable brand Weston, will set up a manufacturing unit for LCD TV sets at Oragadam in Tamil Nadu. According to Dixon’s managing director Sunil Vachini, “The 200,000 units per annum plant will service the Southern markets, while the company’s other LCD TV plant at Uttarakhand (having annual capacity of 100,000 units) will serve the remaining markets.” Once operational, the plant will

start making the 48.3cm (19-inch) LCD TVs, which will be sold at Rs 10,000.

Philips Electronics India moves to new office Philips Electronics India has moved to its new office in Gurgaon. Based on the concept of work place innovation (WPI), the new workplace is part of the company’s approach to integrate business processes and leverage scale and synergies across organisation. Previously, Philips had its offices spread across Pune, New Delhi and Mumbai. Working from one office, at one location, will offer employees an opportunity to communicate and interact across divisional and functional boundaries. According to Gerard Kleisterlee, president and CEO, Royal Philips Electronics, “The new Philips India office will be a trendsetter in work space design and ways of working, supporting teams in their commitment to scale up Philips’ presence in India.”

Moser Baer to install rooftop solar PV in Surat Moser Baer Photovoltaic (MBPV) has won a contract from roads and buildings department of Gujarat to set up what the company calls one of India’s largest rooftop solar photovoltaic (SPV) installations in Surat. The SPV system, of approximately 135 kilowatt-peak (kWp) installed capacity, will run a 40kW load for ten hours every day and charge a battery bank of 6000 ampere hours. Work on the project has already started, and the complete system will be commissioned by April 2009. MBPV will also manage the operations and maintenance of this site for seven years.

RCom adds five million new subscribers Reliance Communications has added five million new wireless subscribers on its network during January 2009. With this achievement, the company claims to have become India’s first and world’s first (apart from China) to add five million new subscribers in a span of 30 days, on its fully-IP enabled, next-

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generation wireless network. The entry of Reliance Mobile in the GSM segment has led to an expansion of the market, with the company seeing a 285 per cent rise in new subscriber additions, within the first month of its nationwide GSM rollout.

BEL signs MoU with Boeing and Astra Microwave Defence PSU Bharat Electronics Limited (BEL) has signed an MoU with Boeing to jointly develop an analysis and experimentation centre in India to offer customers the ability to make better informed decisions in modernising India’s defence forces. “This joint facility will be staffed with local personnel who, with an inherent understanding of India’s challenges, will be most qualified to work with the Ministry of Defence to explore and identify the best ways to satisfy their capability needs,” said I.V. Sarma, director-R&D, BEL. Working together, BEL and Boeing will develop in-country processes that allow for the development of local intellectual property as well as integration of other non-US products into our environment. In another development, BEL and Astra Microwave Products, a provider of RF and microwave components and sub-systems for critical defence and civilian applications, have signed a memorandum of understanding (MoU) to form a joint venture company. The joint venture will design, develop, prototype, manufacture, and market RF and microwave products for use in defense, space and telecommunications.

HP India partners with TERI Hewlett Packard (HP) India, in partnership with The Energy and Resources Institute (TERI), has launched the ‘Hewlett Packard–TERI Schools’ initiative to improve environment projects in schools. As part of the project, HP India has awarded a grant of $250,000 comprising cash and technology resources to TERI for the programme. The primary objective of this partner-

Calendar of Forthcoming Electronics Fairs/Exhibitions/Seminars Name, Date and Venue

Topics to be covered

Contact address for details

CeBIT 2009 March 3-8, 2009 Hannover, Germany

World’s leading event for software, IT and communication

Geeta Bisht Manager-International Fairs Hannover Fairs India Pvt Ltd B-303 Dynasty Business Park Andheri-Kurla Road Chakala, Andheri East, Mumbai 400059 Fax: (022) 40050683; Phone: 40050681, 82 E-mail: [email protected]; Web: hf-india.com

Information Management Technical conference on Technical Conference 2009 IM software (IMTC 2009) March 4-6, 2009 Hotel Le Meridian, Bangalore

For registration, contact: Bangalore: 09322302220; Chennai: 09381506258; Hyderabad: 09391351766; Mumbai: 09373466010; Delhi: (011) 32921868 E-mail: [email protected]

The 3rd World Mobile Summit & Sourcing Fair The 5th China Int’l Mobile Sci-Tech Exhibition March 6-7, 2009 Shenzhen Convention & Exhibition Center, China

Events on the worldwide achievement of the mobile phone industry supplier chain

Rebecca Lee Room 629, West Tower Tian’an High-Tech Plaza Phase II, Futian Distt., Shenzhen, China Fax: (86755) 83293923, 83297552 Phone: 82507486, 83293923 E-mail: [email protected] Web: smca.org.cn

Open Source India Tech Days 2009 March 12-14, 2009 Chennai Trade Centre Chennai

India’s biggest open-source event

Abhay Kumar EFY Enterprises Pvt Ltd D-87/1, Okhla Phase-1, New Delhi 110020 Fax: (011) 26817563; Phone: 26810601, -02, -03 E-mail: [email protected], [email protected]

17th Convergence India 2009 March 18-20, 2009 Pragati Maidan, New Delhi

South Asia’s largest ICT event

Bunny Sidhu, Vice President Exhibitions India Pvt Ltd 217-B, Okhla Industrial Area, Phase III New Delhi 110020 Fax: (011) 42795098/99 Phone: 42795000 (Board)/42795031 (Direct) E-mail: [email protected] Web: convergenceindia.org

IT India Fair, New Delhi March 26-29, 2009

Fair on computer hardware, computer systems, application software, network management and technologies, SAP and ERP solutions, computer peripherals, consumables, etc

India Trade Promotion Organisation Pragati Bhawan, Pragati Maidan New Delhi 110001 Fax: (011) 23371492; Phone: 23371540 E-mail: [email protected], [email protected] Web: indiatradefair.com

International CTIA Wireless 2009 Global showcase of the April 1-3, 2009 latest products and Las Vegas Convention Center innovations in Las Vegas, Nevada, USA wireless telecom

Tulika Sen Phone: (022) 42300800 E-mail: [email protected] Jignesh Khamar Phone: (022) 42300800 Ext: 801 E-mail: [email protected]

Global Sources Electronics & Electronics and Components China Sourcing Fair components fair April 12-15, 2009 AsiaWorld-Expo (next to the Hong Kong Airport)

Register online: www.chinasourcingfair.com

GITEX Saudi Arabia 2009 April 19-23, 2009 Riyadh International Exhibition Centre, Saudi Arabia

8th international information technology exhibition

Vaishali Dua India representative—GITEX Saudi Arabia 2009 Falcon Infocomm Pvt Ltd 1207, Kailash Building K.G. Marg, New Delhi 110001 Fax: (011) 23323953; Phone: 23324288 E-mail: [email protected]

Connect 2009 May 5-7, 2009 Karachi Expo Centre Karachi, Pakistan

4th information and communications technology exhibition and conference

Pegasus Consultancy (Pvt) Ltd 2nd Floor, Business Centre Mumtaz Hassan Road, Karachi, Pakistan Fax: (9221) 2410723 Phone: 111734266 (Pegcon) E-mail: [email protected] Web: pegasus.com.pk

Edutech Expo 2009 June 13-14, 2009 Pragati Maidan New Delhi

Hundreds of educational institutions offering professional courses and training under a single roof

EFY Enterprises Pvt Ltd D-87/1, Okhla Industrial Area, Phase-1 New Delhi 110020 Fax: (011) 26817563; Phone: 26810601-03 Continued on page 121

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Continued from page 120

Calendar of Forthcoming Electronics Fairs/Exhibitions/Seminars Name, Date and Venue

Topics to be covered

Contact address for details

Global Sources Electronics China Sourcing Fair June 14-16, 2009 Dubai International Convention & Exhibition Centre

Electronics fair

Register online: www.chinasourcingfair.com

EnterpriseIT2009 June 16-19, 2009 Singapore Expo CommunicAsia2009 June 16-19, 2009 Singapore Expo

The 6th international information technology exhibition and conference for the enterprise The 20th international communications and information technology exhibition and conference

Agnes Leung Senior Project Manager (Communications Events) No. 1, Jalan Kilang Timor # 09-02 Pacific Tech Centre Singapore 159303 Fax: +65 6233 6633 Phone: +65 6233 6638 E-mail: [email protected] Web: sesallworld.com

InteractiveOne June 16-19, 2009 Singapore Expo

The 3rd international interactive, digital media and entertainment exhibition and conference

Media Exposition & Events 112-A, Sant Nagar, (GF), East of Kailash New Delhi 110065 Fax: (011) 41620861 Phone: 26445191/2

Robotics & Automations World Expo 2009 Aug. 20-23, 2009 Pragati Maidan New Delhi

Exhibition on automation industry

KMG Business Technology C-3/803, Anushruti Tower Opp. New York Tower, New Thaltej Circle, S.G. Road, Thaltej, Ahmedabad 380059 Fax: (079) 26463145; Phone: 32410602 E-mail: [email protected]

Smartcards Expo 2009 Sep. 10-12, 2009 Pragati Maidan New Delhi

Expo on smart-card technology and applications

Electronics Today 104, Andheri Industrial Estate Off. Veera Desai Road, Andheri (W) Mumbai 400053 Fax: (022) 26730547/48; Phone: 26730869-71 E-mail: [email protected]

Expo Comm India 2009 Sep. 17-19, 2009 Pragati Maidan Exhibition Centre New Delhi

Exhibition and conference on ICT

Bimal Ghosh, Project Head Inter Ads Exhibitions Pvt Ltd 859, Phase-V, Udyog Vihar Gurgaon 122016, Haryana Fax: (0124) 4381162; Phone: 4524200, 4524106 E-mail: [email protected]

Mobile Asia 2009 Oct. 2-5, 2009 Pragati Maidan New Delhi

Platform for mobile handset companies, mobile accessories, VDS companies

International Venture Partners A-20, Lajpat Nagar-II, New Delhi 110024 Phone: (011) 29840908 E-mail: [email protected]

Global Sources Security Products China Sourcing Fair Oct. 12-15, 2009 AsiaWorld-Expo, Hong Kong

Security products fair

Register online: www.chinasourcingfair.com

Electronics & Components China Sourcing Fair Nov. 20-22, 2009 Bombay Exhibition Centre

Electronics and components fair

Register online: www.chinasourcingfair.com

India Telecom 2009 Dec. 3-6, 2009 Pragati Maidan New Delhi

Event on communication arcade, customer premise equipment, IT corridor

Federation of Indian Chambers of Commerce and Industry Federation House, Tansen Marg New Delhi 110001 Fax: (011) 23320714; Phone: 23738760 E-mail: [email protected]

Energy Tech, New Delhi Dec. 14-17, 2009 Pragati Maidan New Delhi

Event on emerging power technologies, sustainable energy solutions, alternative energy sources, energy management and trends

India Trade Promotion Organisation Pragati Bhawan, Pragati Maidan New Delhi 110001 Fax: (011) 23371492; Phone: 23371540 E-mail: [email protected], [email protected] Web: indiatradefair.com

International CES 2010 Jan. 7-10, 2010 Las Vegas, Nevada, USA

International consumer electronics fair

Registration Help (inside US): [email protected], 866-233-7968 Registration Help (outside US): [email protected], 301-694-5243

Look up under ‘Events’ section in www.electronicsforu.com for a comprehensive list

Since this information is subject to change, all those interested are advised to ascertain the details from the organisers before making any commitment.

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ship is to create a motivated force of students—leading to cleaner and greener school campuses—and initiate ecologically beneficial initiatives in the areas of energy, e-waste management and greening of neighbourhoods. The initiative will help primary and secondary schools in Bengaluru, Chennai and Delhi to take practical action to save energy and water while reducing their utility bills. It will support the schools directly with ideation, as well as in implementing their environmental initiatives. The initiative also involves providing HP technology to the schools, which will enable them to network with other schools and share best practices.

Kshitij 2009 Students from all over India and neighbouring countries made their presence felt at Kshitij 2009, the annual techno-management symposium of IIT Kharagpur. Kshitij 2009 was host to a lot of events in which the participants had a chance to showcase their knowledge in the fields of electronics, coding, hardware designing, aeronautics, robotics, mechanical engineering, chemical engineering and various other fields of engineering, technology and also management. Of the forty odd events conducted during Kshitij 2009, the following events were a special attraction for the students of the department of electronics and electrical engineering all over the country: Anadigix (the electronics’ circuit design competition) and Eureka (the technical paper presentation competition).

LG may increase R&D investment LG Electronics has announced its long-term business plan and strategy to succeed in the current business environment. Yong Nam, CEO of LG Electronics, confirmed that the company would not reduce—and could even increase—its investment in R&D, marketing, branding and design. The company has intensified its efe l e c t ro n i c s f o r yo u • m a r c h 2 0 0 9 • 1 2 1

Snippets Mobile number portability by August! The Department of Telecommunications (DoT) is planning to start mobile number portability (MNP) in major Indian cities by August and in the remaining cities by the end of this year. Bids had already been invited for providing the MNP switches. The faster penetration of 3G would enable people to use the services with greater accessibility.

BSNL rolls out 3G services Bharat Sanchar Nigam Limited (BSNL) has launched next-generation 3G mobile services in the country even as the private operators are still waiting to get spectrum through auction process. BSNL and public-sector unit MTNL (for Delhi and Mumbai) were given 3G spectrum last year ahead of auction for private players keeping in mind the cumbersome tendering process involved in the public-sector procurement system.

By 2011, Kerala to get ten IT parks It will be a matter of time when Kerala will develop as the preferred IT destination in India, as the state would soon be equipped with over ten IT parks. According to Ajay Kumar, secretary, Information Technology, Kerala, the hub-and-spoke model of development being undertaken in Kerala’s information technology sector will enable the state to equip itself with over ten IT parks at various destinations by 2011.

Samsung to invest in Chennai and Noida facilities Samsung India is going to invest $20 million in its Chennai and Noida facilities this year to expand operations. Last year, the company had invested $200 million as part of its global expansion plans. It had reported a turnover of $1.7 billion last year and has projected to grow 27 per cent approximately this year.

China Mobile considering acquisition in India China Mobile, which has the world’s largest number of subscribers (457 million), is considering an acquisition in India for expansion. The company, however, might face hurdles in India over security issues, especially because it has operations in Pakistan.

forts to increase market share despite the volatile economic situation. To achieve this, LG has reorganised its business portfolio to focus on areas with longerterm growth potential and profitability. Partnerships will continue to be a key element of the company’s marketing activities to elevate its brand position. LG will continue to invest in future growth engines such as solar power, commercial air-conditioners and B2B solutions.

discussions of how the two companies can best deploy their resources and expertise, continue to negotiate in good faith and have set June 30, 2009 as the target date by which to enter into a definitive agreement to establish a joint venture that will be mutually beneficial for both companies. Sharp plans to start operating its new LCD panel factory in Sakai-City, Osaka, by March 2010 as originally scheduled.

Sharp, Sony postpone LCD production Faced with changes in the world economy, Sharp and Sony have decided to postpone the establishment of their joint venture to produce and sell large-size LCD panels and modules, until March 2010. The duo will, through continued

LG may shut down PC business, to focus on low-cost handsets

LG is likely to shut down its PC business globally owing to lower market response amidst economic slowdown. The company’s IT vertical contributes only 10 per cent to its overall revenues, and it will not have any impact on its

electronics consumer market. The company, however, plans to focus on low-end handset emerging markets this year with the aim of boosting its global handset market share to more than 10 per cent from 8.5 per cent last year. “The global handset market in 2009 is expected to shrink by about 5 per cent to 10 per cent led by weaker demand in developed countries,” said Skott Ahn, president of LG’s mobile communications division. “But emerging nations are expected to grow over 10 per cent (this year). Thus, we have to focus on emerging markets to maintain our growth,” Ahn said. Ahn also said that the company is targeting to increase the proportion of low-end handsets it sells to more than 20 per cent this year, from around 5 per cent in 2008. Low-end handsets refer to mobile phones that are typically sold to consumers for less than $100.

Forecast for PV cell and module manufacturing equipment

According to VLSI Research Inc., the photovoltaic (PV) cell and module manufacturing equipment market for all cell technologies reached a value of $4.4 billion in 2008. Growth in the market is expected to slow to 8 per cent in 2009 as demand for cells starts to cool and smaller manufacturers struggle to secure the financing necessary to fund the next round of expansion. However, the outlook for equipment suppliers this year varies by cell technology. Providers of equipment for thin-film cell technologies will experience strong growth in revenues in 2009 due to large order backlogs and long customer acceptance times. In contrast, suppliers of equipment for silicon wafer cell manufacturing are expected to see a decline from 2008 levels as customers with excess capacity choose to fully ramp existing facilities before committing to new equipment. Overall, this results in growth of 8 per cent for the year.

Check efytimes.com for more news, daily 1 2 2 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

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Interview

Thin-film modules reduce the cost of energy generation

 Dr Randhir Thakur senior vp and gm of Applied’s SunFab Thin Film Solar and Display Business Group

Applied Materials, Inc. (AMAT) is the global leader in nanomanufacturing technology solutions with a broad portfolio of innovative equipment, services and software products for fabrication of semiconductor chips, flat-panel displays, solar photovoltaic cells, flexible electronics and energy-efficient glass. Dr Randhir Thakur, senior vice president and general manager of Applied’s SunFab Thin Film Solar and Display Business Group, was recently in India to announce that Moser Baer India is their first Indian customer that will start volume production of thin-film photovoltaic (PV) modules. On this occasion, Dr Thakur, along with Rajiv Arya, CEO of Moser Baer Photovoltaic (MBPV), spoke to EFY’s Uma Bansal about the solar energy market and Applied Material’s advanced SunFab solar technology as a cost-effective option for clean renewable energy

Q

What is the current state of the solar energy technology market in India and globally? RT: According to Solar Buzz, annual growth of the global photovoltaic (PV) market has averaged a compound rate of just over 47 per cent since 2003 and strong growth is expected into the foreseeable future. In 2007, world PV cell production was 3036 MW for crystalline silicon and 400 MW for thin-film. Thin-film cell production now represents 12 per cent of global PV cell production and this percentage is expected to increase. India is regarded as one of Asia’s fastest growing economic powerhouses and, as a result of this growth, there is increased demand for electricity. As a matter of fact, India is the world’s third largest consumer of coal, which accounts for more than half of India’s total energy generation. However, even the current consumption of coal is not enough to meet India’s demands. Of the estimated 132 GW of energy capacity in India, only 110 MW is derived from solar. Therefore the increased demand for electricity, coupled with the dwindling supply of fossil fuels, represents significant opportunities for all sources of renewable energy, especially solar.

Q

What are the benefits of thin-film PV over crystalline silicon cells? RT: Each technology is well positioned to serve a unique market segment. For space-constrained areas such as residential and small commercial rooftops, crystalline silicon panels are ideal because of their higher efficiency. For large commercial and utility-scale solar farms, thinfilm offers tremendous cost-saving benefits that will help drive the cost of solar power generation toward grid parity 1 4 0 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

 Rajiv Arya CEO of Moser Baer Photovoltaic (MBPV)

and beyond. Thin-film also has some technical advantages for these types of deployments. For example, when a solar cell is shaded, the output of the entire module decreases. With the unique size of the SunFab produced panels, the cell is as long as the module—up to 2.6 metres in length. This makes it very difficult for any shading to cover the entire cell to the extent that it decreases power production. Additionally, solar panels overall can lose power output when they reach extremely high temperature, like in very sunny places on hot summer days. Thin-film modules retain more of their power output than crystalline silicon under these conditions because of differences in the materials that make the cell.

Q

Which products use the thin-film PVs and what are the market opportunities for these products? RT: Any product can use thin-film PVs. From applications as small as calculators to utility-scale installations and building integrated photovoltaics, the market opportunity is virtually endless.

Q

How does Applied Materials’ technology benefit Indian customers? RA: The thin-film line that we have established with Applied Materials is a fully-integrated PV module production line that delivers leading-edge solar manufacturing capability using advanced engineering, process equipment, automation and other key supporting technologies. The technology will provide innovative PV products that can significantly reduce electric power and utility costs and provide a costeffective option for clean and renewable energy. Thin-film modules can facilitate reduction in the cost of energy generation for two reasons: thin-film amorphous silicon is more appropriate for warm climates and large w w w. e f y m ag . co m

Interview modules (5.7 m2) reduce the overall balance of system costs. The net effect is that the customer gets power cheaper.

Q

The technology is expensive. How long will it take to make it affordable? RT: Solar technology has already achieved grid parity in several areas today. For example, California’s peak summer electricity rates hover above 35 cents/kWh in certain places, which is more expensive than unsubsidised solar power generated today at about 30 cents/kWh. In addition, solar power can be distributed across the grid to relieve pressure on critical substations or transmission lines without the time or expense of re-wiring new transmission or distribution facilities. As a resource for energy generation, solar is incredibly abundant. Every day, the sun provides more energy than we need for the planet. What this means is that from a cost, availability and rapid-deployment perspective, solar power makes sense right now. Additionally, thin-film technology dramatically reduces the amount of silicon needed to produce a module, thereby reducing costs. By applying our company’s 40 years of experience in driving down the cost of integrated circuits, and more recently flat-panel displays, we’re also bringing advances in deposition process, automation and factory efficiency to the thin-film production environment. All of these efforts further help to drive down the price of solar power generation.

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Q

What are your future plans with Applied Materials? RA: We have just started production at this 40MW capacity line, which is the largest thin-film solar line in India. This single-junction line has demonstrated the highest production capacity to date for manufacturing the world’s largest (2.2×2.6m2) solar modules. Next, we are building the second plant in Greater Noida with AMAT. This is a 65MW tandem junction plant with the same large-footprint module. The full-size product will generate greater than half-a-kilowatt per panel. We are also in advance stages of discussions with AMAT on our 500MW thin-film plant in Chennai.

Q

What trends do you foresee in the Indian solar PV space? RA: The technological landscape of solar power is impressive: Crystalline silicon is the most mature technology and has the largest market share, but it is in short supply. Thin-film is a maturing technology and poised for high growth. Also, it has the potential to reduce costs significantly. Concentration PV is being rapidly developed for the market and it has significant cost-reduction potential as well. Finally, nanotechnology is in the R&D phase and it has tremendous cost-reduction potential. As a trend we see more installations of solar PV for small, medium and large off-grid applications and large solar farms for on-grid applications. Our effort is to work diligently in all PV technologies and bring the solar dream to fruition to meet India’s energy needs.

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bookshelf

Fuzzy Logic and Fuzzy Decision Making The fuzzy logic provides an inference structure that enables appropriate human reasoning capabilities. On the contrary, the traditional binary set theory describes events that do or do not occur. This book helps academicians, researchers and students in the fuzzy set theory and fuzzy decision making. It is written as a textbook for the course in fuzzy logic and its application at graduate, By: Dr G. Kannan postgraduate and doctorate Published by: Galgotia Publications levels. Pvt Ltd, 5, Ansari Road, Daryaganj, New Delhi 110002 The book is divided into Pages: 186; Price: Rs 200 two parts. The first contains fuzzy sets, fuzzy relations, membership function and fuzzy decision making. The second part covers application of fuzzy logic, introduction to optimisation techniques and introduction to neural network.

An Introduction to Mixed-Signal IC Test and Measurement This textbook is useful for advanced undergraduate and graduate-level students as well as engineering professionals. It assumes a solid background in analogue and digital circuit as well as working knowledge of computers and computer programming. A background in digital signal processing and statistical analysis is also helpful. The book covers the testing of both analogue and mixed-signal By: Mark Burns, circuits including many examGordon W. Roberts ples. Digital testing is covered, Published by: Oxford University Press, YMCA Library Building, but not extensively. Examples Jai Singh Road, and illustrations using state-ofNew Delhi 110001 the-art industrial technology Pages: 684; Price: Rs 495 enrich the presentation throughout. In considering the applications of this technology, the testing of large-scale mixed-signal circuits and individual circuits is introduced.

Robot Programmer’s The DSP Handbook: Algorithms, Applications Bonanza and Design Techniques This book is aimed at those This book is a hands-on guide to digital signal processing (DSP) and its applications. It provides you with the training, tools and building blocks necessary to assess and unlock the potential of DSP in your own products and services. Mathematical analysis is provided as clearly and concisely as possible and real-time examples are liberally provided throughout the text. The book includes By: Andrew Bateman, Iain Paterson-Stephens numerous design tips, describing the ‘tricks of the trade.’ Also given Published by: Dorling Kindersley (India) Pvt Ltd, 482, F.I.E., are many written examples and Patparganj, Delhi 110092 descriptions of devices for most Pages: 664 Price: Not mentioned mainstream DSP manufacturers. Real-time audio and visual DSP examples enable you to experience the power and application of DSP from the very beginning. Four algorithm-packed ‘toolboxes’ allow easy access to particular algorithms/models of interest. The accompanying CD contains related applications. 1 4 2 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

who are ready to go beyond just building robots and start programming them to perform useful tasks. Using the versatile RobotBASIC programming language, you’ll discover how to prototype your creative ideas using the integrated mobile robot simulator and then port your finished programs to nearly any hardware/ By: John Blankenship, software configuration. You can Samuel Mishal even use the built-in wireless Published by: BPB Publications, protocol to directly control realB-14, Connaught Place, New Delhi 110001 world robots that can be built Pages: 396; Price: Rs 297 from readily available sensors and actuators. The RobotBASIC program, along with all the programs in this book, can be downloaded from ‘www.RobotBASIC. com.’ Adaptable and customisable programs help to solve realistic problems. Appendices detail RobotBASIC’s extensive commands and functions as well as the integrated programming environment. w w w. e f y m ag . co m

subject & organisation index

Subjects Covered in This issue Subject

Page No.

Subject

Page No.

Subject

Page No.

Subject

Page No.

3D Graphics ....................................................... 24

Hard Drives (NP) ...............................................115

Multimeters (NP) ...............................................115

Software ............................................................... 8

3G . ................................................................... 122

HDTV . ............................................... 28, 30, 32-34

Music System ..................................................... 70

Solar PV ....................................................119, 122

Amplifier IC (NP) ...............................................116

HDTV Broadcast ...............................................118

Optical Clocks .................................................... 20

Solar-powered Phones . ..................................... 22

Battery Charging ........................................... 92-98

Hearing Aid (CI) . ................................................ 85

PC Sales ...........................................................118

Telecom .............................................................118

Bluetooth ....................................................112-114

IGBT (NP) . ........................................................116

PC-based Wireless Stepper Motor

Thermometers (NP) . .........................................115

Broadband Router (NP) . ...................................116

In-car Food Warmer (CI) .................................... 84

Control (C) . ................................... 60, 62, 64, 66

Three-Component Flasher (CI) .......................... 83

Cameras, Digital . ..............................................119

Intelligent Transport System . ............................. 25

PCs . ................................................................. 122

Triple Power Supply (CI) .................................... 81

Capacitors .......................................................... 16

Internet ............................................................... 26

Personal Music Players . ................... 73, 74, 78-80

TV Data Card ..................................................... 24

Career, Power Electronics . .............. 36, 38, 40, 42

IPTV ................................................................... 72

Pianos ................................................................ 68

Video Cards (NP) ..............................................117

Charger, Mobile .................................................. 20

IT Parks ............................................................ 122

Power Backup ...................................................119

Video Encoder (NP) ..........................................117

Cleaner, Air-Dust (NP) . .....................................116

Keyboards .......................................................... 68

Power Meter ....................................................... 24

Water Pump Controller (CI) ................................ 82

Condensers ........................................................ 16

LAN-based Online Exam (SW) . .................... 87-90

Projector, Ultra-Short-Throw . ............................. 72

White Light for Refrigerators (CI) ....................... 85

Datasheets, Device ........................... 100, 102-106

LCD TV . ..............................................68, 119, 122

Projectors, DLP .................................................. 70

Wi-Fi ................................................................... 24

Desktop PCs ...................................................... 72

Microcontroller-based Ring Tone

Projectors, Multimedia . ...................................... 68

Windows Phones . .............................................. 22

DSPs ................................................................ 142

Player (C) ..................................... 52, 54, 56, 58

Robotics ........................................................... 142

e-books . ............................................................. 20

Mobile Number Portability ................................ 122

Robots ................................................................ 20

Energy Saver (NP) ............................................115

Mobile Phones . .................................................. 70

Salary Survey ................................................ 43-46

Flexible Circuits ............................................. 48-50

Mobiles ............................................................... 26

Semiconductor ..................................................118

Foot Switch (NP) ...............................................116

Mobiles, Touchscreen . ....................................... 16

Sensor (NP) . .....................................................116

Frequency Counter . .................................. 107-110

Monitor, TFT (NP) . ............................................117

SEZ ...................................................................119

Abbreviations C=Construction........... CI=Circuit Idea SS=Software Section NP=New Products

Organisations Covered in This issue Organisation

Page No.

Organisation

Page No.

Organisation

Page No.

Organisation

Page No.

A.V. Systems ...................................................... 45

Dixon .................................................................119

Microchip ............................................................ 98

Samsung India ............................................. 32, 34

Airtel ................................................................... 72

Doordarshan . ....................................................118

Microsoft . .......................................................... 22

Sandisk . ............................................................. 74

Aplab ............................................................ 38, 40

E Power Engineering . .......................................116

Moser Baer . ..............................................117, 119

Sanyo Semiconductor .......................................116

Apple ............................................................ 73, 74

Edimax ..............................................................116

Moser Baer Photovoltaic .................................. 141

Seagate .............................................................115

Applied Material . .............................................. 140

Fortune Marketing .............................................115

Motorola ............................................................. 26

Sharp . .............................................................. 122

APW ................................................................... 42

Frost & Sullivan .................................................118

MTNL . .............................................................. 122

Sharp Business Systems (India) ............ 33, 34, 68

Arrow Electronics ............................................... 38

Google . ........................................................ 24, 25

NDS . .................................................................118

Softspin .............................................................. 26

Astra Microwave . ............................................. 120

GSMA ................................................................ 22

Neural Systems .................................................. 46

Sony ........................................................... 74, 122

Atoall.com . ......................................................... 26

Hart Scientific ....................................................115

NIST ................................................................... 20

Sony India ........................................ 30, 34, 68, 79

Axis Communications . ......................................117

Hewlett Packard (HP) . ....................................... 72

Nokia .................................................................114

STMicroelectronics . ....................................24, 116

BenQ .................................................................. 70

Hitachi ................................................................ 72

Parker Power Systems . ............................... 36, 38

Supertron Electronics ........................................115

Bharat Electronics Ltd (BEL) ............................ 120

Hitachi Home Electronics ............................ 28, 34

Philips . ......................................................... 74, 80

Teknic ................................................................116

Bharti Airtel ........................................................118

HP India . .......................................................... 120

Philips Electronics .............................................119

Toshiba ............................................................... 74

Boeing .............................................................. 120

Humx .................................................................. 78

Plastic Logic ....................................................... 20

Transcend . ........................................................115

Bose ................................................................... 70

Idea ...................................................................118

Pressmart ........................................................... 26

TTL Technologies ..............................................115

BSNL ................................................................ 122

iRiver .................................................................. 74

R.S. Electronics . ...............................................116

Videocon ...................................................118, 119

Cambridge Silicon ............................................. 24

ISA . ...................................................................118

Radio .................................................................. 24

ViewSonic . ........................................................119

Casio India ......................................................... 68

Kchiloo . ............................................................ 107

RCA .................................................................... 74

VLSI Research ................................................. 122

Cecon Pollutech ................................................116

Kingston ............................................................117

Reliance Communications . .......................118, 119

ZTE . ................................................................... 24

China Mobile .................................................... 122

LG . ..................................................................... 70

Renesas ............................................................118

Conzerv .............................................................115

LG Electronics .......................................... 121, 122

Robert Gorden Univ. . ......................................... 20

Creative Labs ..................................................... 74

MAIT ..................................................................118

Samsung ...............................22, 74, 118, 119, 122

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Advertisers’ Index Accord Communication (www.accordcom.com).............................69

Intron (www.intronresistors.com).......................................................127

Advance Tech Services Pvt Ltd (www.advancetechonline.in)........6

Kaku Enterprises (www.toroidalhouse.com)...................................128

Omron Electronic Components Pte Ltd (http://ecb.omron.com.sg)................................................................143

Agilent Technologies India P Ltd (www.agilent.com)....................39

Keithley (www.keithley.com).................................................................14

Pantech Solutions Pvt Ltd (www.pantechsolutions.net)...............126

Bharat Electronics Ltd (www.bel-india.com)......................................63

Keptek Power Controls Pvt Ltd............................................................103

Penram Intl. Publishing (India) (www.penram.com)......................79

Binay Opto Electronics Pvt Ltd  (www.binayLED.com)...............111

Kitek TechnologiesPvt Ltd (www.kitektechnologies.com)..........128

Pla Components (www.plarelays.com).............................................129

Chetan Cabletronics Pvt Ltd (www.chetancabletronics.com).....124

Kits.................................................................................................................141

Qmax Test Technologies P Ltd (www.qmaxtest.com)..................117

Deltronik Engineers..................................................................................128

Lattice Semiconductor.................................................................................9

Radhika Agencies.....................................................................................125

Dynalog (India) Ltd (www.dynalogindia.com)...................................5

Linkwell Telesystems Ltd  (www.visiontek.co.in)..............................7

Rajmane Telectric P Ltd (www.rajmaneteletric.com).......................71

Edutech..........................................................................................................91

Live Wire Electronics (www.livewireinfo.com).................................21

Relaytronics/Insight Innovation (www.relaytronics.com)............37

ei-labz (www.emblitz.com)......................................................................23

Mac Net Technology................................................................................139

RS Components & Controls (I) Ltd (www.rsindia.com)...................3

Electromech (www.electromechindia.com)......................................128

Macroblock....................................................................................................49

S.M Semiconductors (www.aplusindia.com)...................................139

Electronic Annual Guide...........................................................................55

Mastech Delhi.............................................................................................127

Seoul Semiconductor (www.seoulsemicon.com)..............................11

Electronic India..........................................................................................138

Max Electronics (www.trontekindia.com)..........................................80

Siemens Ltd  (www.siemens.com/enterprise)...................................51

Electronic Project.......................................................................................101

Max Electronics (www.trontekindia.com)..........................................97

Signet (www.signet-instruments.com).................................................10

Electronics Bazaar.......................................................................................99

Max Technology & Co. (www.maxtechnoloindia.com)...............148

Solar EnergieTekchnik Ltd (www.infinitsolar.in)...........................126

EnterpriseIT 2009 (www.communicasia.com)...................................93

MDR Electronics (www.mdrelectronics.com)....................................33

Sparr Electronics Ltd (www.sparrl.com).............................................31

Falcon Electro-Tek Pvt Ltd  (www.falconindia.biz)..........................29

Meco Instruments Pvt Ltd (www.mecoinst.com).............................35

Subscription Form ........................................................................75, 76, 77

Farnell Electronics India Pvt Ltd (www.farnell.in)...........................15

Millenium Technologies..........................................................................129

Sumitron Exports Pvt Ltd (www.sumitron.com)..............................19

Frontline Electronics Pvt Ltd (www.Frontline-Electronics.com)..10

Miracle Electronic Devices P Ltd (www.toroidal.com)..................101

Tadiran Batteries (www.tadiranbat.com)............................................61

Fujitsu Microelectronics Asia Pte Ltd (www.fujitsu.com)..............59

Mithra Electronics.......................................................................................57

Taiyo Yuden (S) PL (www.ty-top.com)..............................................101

Gunze Electronics USA Corp..................................................................89

Mornsun Guangzhou Science & Technology Co., Ltd....................17

Tektronix (India) Ltd (www.tektronix.com/2170)..........................147

Hitachi India Trading Pvt Ltd (www.hitachi.co.in)..........................27

National Instruments India (www.ni.com)...........................................2

TTL Technologies Pvt Ltd (www.ttlindia.com).................................34

Inde Enterprises...........................................................................................13

National Semiconductor (www.national.com)..................................53

upsinverter.com.........................................................................................123

Indian Service Machine (www.ismbangalore.com).........................71

Neelam Import Pvt Ltd...........................................................................129

VPL Infotech & Consultants (www.vplinf.com)...............................47

Innovators and Simplifiers.......................................................................30

Open Source Tech Days............................................................................41

Xtend Technologies Pvt Ltd (www.xtendtech.com)........................65

Instt. of Mobile Phone Tech. (www.britco.co.in)................................71

Omniscient Electronics Pvt Ltd 

Young India Appliances (www.youngindiaappliances.com).....139

Integrated Services & Consultancy (www.instek.com).................146

(www.omniscientelectronics.net).......................................................25

EFY Magazine Attractions During 2009

MONTH

Tech Focus SURVEY/EFY REPORT

eStyle Buyers’ Guide

January

E-waste Management

Industry Forecasts

Which Camera Phone?

February

Artificial Space Satellites

Budget Memorenda

Which DTH?

March

High Definition Television

Salaries in Electronics Industry

Which Personal Music Player?

April

LED Lighting

Embedded Systems

Which Watch?

May

Electronic SMT Components

Chip, Circuit & Product Designers

Which UPS/Inverter?

Connect 2009, Karachi

June

New T&M Devices

India’s Top Training Institutes

Which Notebook?

Communic Asia 2009, Singapore EduTech 2009, New Delhi

July

Mobile Entertainment

Automotive Electronics Industry

Which TV?

August

The Open Source: Hardware? SMT in India

Digital Camera/Camcorder?

September

IPTV

Industrial Automation

Home Security System

October

What’s New in Wireless

India's Top 100 Electronics Companies Which DVD Player?

November

Contract Manufacturing

T&M Manufacture in India

Which Home Theatre?

China Electronics Fair, Shanghai

December

Solar Cells: An Update

Indian Solar Energy Industry

Which New Gizmo?

India Telecom 2009, New Delhi

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Trade Fair Participation

Componex Nepcon India, New Delhi, Jaipur Book Fair, Lighting Asia, Mumbai, Automotive Electronics, Bengaluru 17th Convergence India, New Delhi, Infocomm India, Mumbai, Mobile China Expo, Shenzen (China)

ElectronicIndia, Bangalore Globaltronics, Singapore

e l e c t ro n i c s f o r yo u • m a r c h 2 0 0 9 • 1 4 5

1 4 6 • m a r c h 2 0 0 9 • e l e c t ro n i c s f o r yo u

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