Cap 13

&LUFXLWHEDVFXODQWHELVWDELOHFXSRU LORJLFH

1. Bistabilul elementar 3ULQ DQDORJLH FX XQ ELVWDELO FX WUDQ]LVWRDUH VH SRDWH FRQVWUXL FLUFXLWXO EDVFXODQW ELVWDELO FX SRU L

logice, fig.1.

Fig.1 Circuite basculante bistabile 3HQWUXDSHUPLWHFRPDQGD ELVWDELOXOXLGH OD LQWU ULFHOHGRX LQYHUVRDUHVH vQORFXLHVFFX FLUFXLWH 6$818 VDX 6,18  6H RE LQ FLUFXLWHOH EDVFXODQWH ELVWDELOH  GLQ ILJ FDUH YRU IL GHQXPLWH

bistabile elementare.

Fig.2. Bistabile elementare . a. cu nivel activ 0 ( construit cu SI-NU ) b. cu nivel activ 1 ( construit cu SAU-NU) &HOHGRX LQWU ULDOHELVWDELOXOXLVXQW

R = Reset = “ punere pe zero” = “resetare” . S = Set = “punere pe unu “ = “setare “. ,HúLULOH VDOH VXQW 4 úL 4¶ úL VXQW FRPSOHPHQWDUH FX H[FHS LD VW ULL QHSHUPLVH $WXQFL FkQG VH VSXQHF ³ELVWDELOXOHVWHvQVWDUHD´VHYDvQ HOHJHIDSWXOF LHúLUHDVDQRWDW FX4HVWHvQVWDUHD úLLPSOLFLWLHúLUHD4¶HVWHvQVWDUHD  6H REVHUY  FRQVWUXF LD VLPHWULF  D ELVWDELOHORU úL QRWDUHD DOHDWRDUH D LHúLULORU ORU 4 úL 4¶ ,QV RGDW  QRWDWH LHúLULOH LQWU ULOH 5 úL 6 QX PDL SRW IL QRWDWH DOHDWRU SR]L LRQDUHD ORU GHFXUJkQG REOLJDWRULXvQVHQVXOvQFDUHIXQF LRQHD] DFHVWHDGHVHWDUHVDXUHVHWDUH 

&RQYHQ LH

•

:

R LQWUDUH HVWH ³FX QLYHO DFWLY  ORJLF´ GDF  DSOLFkQG  SH DFHD LQWUDUH FLUFXLWXO H[HFXW FRPDQGDUHVSHFWLY RDVWIHOGHLQWUDUHVHYDQRWDFXOLWHUDJUXSXOGHOLWHUH FDUHRGHQXPHúWH I U QHJDUH 

•

R LQWUDUH HVWH ³FX QLYHO DFWLY  ORJLF´ GDF  DSOLFkQG  SH DFHD LQWUDUH FLUFXLWXO H[HFXW FRPDQGDUHVSHFWLY RDVWIHOGHLQWUDUHVHYDQRWDFXOLWHUDJUXSXOGHOLWHUH FDUHRGHQXPHúWH

cu negare . &XDFHDVW FRQYHQ LHVHREVHUY F XQELVWDELOHOHPHQWDUWLS56QXDUHSHUPLV FRPDQGD vQFDUH VHDFWLYHD] VLPXOWDQDPEHOHLQWU ULvQVHQVXOF SHQWUXRDVWIHOGHFRPDQG FHOHGRX LHúLUL4úL

4¶QXPDLVXQWFRPSOHPHQWDUH±YH]LILJLGHHDVH YDUHOXD ODELVWDELOHOHVLQFURQH úLU PvQH QHPRGLILFDWGDF LQWU ULOHQXVXQWDFWLYDWH

2EVHUYD LHQLYHOXODFWLYDOXQHLLQWU ULSRDWHILPRGLILFDWSULQDG XJDUHDXQRULQYHUVRDUHILJ

)LJ6FKLPEDUHDQLYHOXOXLDFWLYDOLQWU ULORUXQXLELVWDELOHOHPHQWDU

*HQHUDOL]DUHFRQVLGHUkQGXQQXP USDUGHSRU L

logice inversoare (NU, SI-NU, SAU-NU ) legate vQ LQHO ILJ VH YD RE LQH XQ FLUFXLW EDVFXODQW

bistabil . Fig.4. Circuit basculant bistabil 3UREOHP &DUHGLQVFKHPHOHSUH]HQWDWHvQ ILJVXQWELVWDELOH " 6  VH QRWH]H LQWU ULOH úL LHúLULOH UHVSHFWkQG WRDWHFRQYHQ LLOHVWDELOLWHPDLVXV

Fig.5 2EVHUYD LH ÌQ PXOWH FLUFXLWH GH PHPRULH HOHPHQWXO GH ED]  HVWH XQ &%% FRQVWUXLW FX GRX WUDQ]LVWRDUH ELSRODUH ILJ VDX FX WUDQ]LVWRDUH 026 vQ DFHVW GLQ XUP  FD] GUHSW UH]LVWHQ H GH VDUFLQ  VH IRORVHVF WRW WUDQ]LVWRDUH 026

eventual complementare - cazul CMOS). &RPDQGD DFHVWRUD GH UHJXO  DUH VWUXFWXUD IXQF LRQDO  FH UHVSHFW  VFKHPD GLQ ILJ 6H UHPDUF  IDSWXO F  DFHVWD  HVWH GH IDSW XQ ELVWDELOHOHPHQWDUWLS56UHDOL]DWFXGRX SRU L 6$818

GRX 

WUDQ]LVWRDUH

UHDDOL]HD] XQ6$8 

Fig.6. Bistabil tip RS cu tranzistoare

vQ

SDUDOHO

2. Bistabilul RS tip latch %LVWDELOHOH HOHPHQWDUHSUH]HQWDWH DQWHULRU VXQW DVLQFURQH  LPHGLDW FH VH DSOLF  R FRPDQG 

tact sau

ELVWDELOXORH[HFXW %LVWDELOXOHOHPHQWDUVHSRDWHFRPSOHWDFXRQRX LQWUDUHQRWDW 

clock (prescurtat T sau CL sau CK ), care are rolul de a stabili momentul vQ FDUH DF

LRQHD]

LQWU ULOH56±ILJ

Fig.7. Bistabil RS latch &RQVWUXF LH

Circuitul este compus din : • SRU LOHGHDFFHVúL • ELVWDELOXOHOHPHQWDUSURSULX]LVUHDOL]DWFXSRU LOHúL )XQF LRQDUH

•

3HQWUX7

SRU LOHGHDFFHVúLVXQWYDOLGDWHúLLQWU ULOH56VXQWSXVHvQOHJ WXU FX

ELVWDELOXO HOHPHQWDU FLUFXLWXO DF LRQHD]  FRQIRUP WDEHOXOXL GH IXQF LRQDUH DO XQXL ELVWDELO56RELúQXLW

•

3HQWUX 7

 SRU LOH  úL  VXQW EORFDWH DX  ORJLF OD LHúLUH  úL DSOLF  ELVWDELOXOXL

HOHPHQWDU    H[DFW FRPDQGD 5

6

 FDUH QX PRGLILF  VWDUHD DFHVWXLD VH VSXQH F

LQWU ULOH56DOHODWFKXOXLVXQWGHFXSODWHGHODELVWDELOXOHOHPHQWDUúLELVWDELOXOLQWU vQ

starea de ]

YRUkUH

ODWFKPHPRUkQGVWDUHDDQWHULRDU 

$ UH]XOWDWR IXQF LRQDUH vQ FDUH LQWU ULOH 56 DX IRVW FXSODWH OD ELVWDELOXO HOHPHQWDU QXPDL SHQWUX SDOLHUXO GH  ORJLF DSOLFDW OD LQWUDUHD GH WDFW 6H REVHUY  GHFL F  WDFWXO FRQWUROHD]  QXPDL PRPHQWXO FkQG IXQF LRQHD]  LQWU ULOH 56 QX úL IHOXO vQ FDUH DFHVWHD DF LRQHD]  úL GH DFHHD VH

sincrone.

VSXQHF LQWU ULOH56VXQWLQWU UL

&RQYHQ LH

•

'DF SRU LOHGHDFFHVVXQWYDOLGDWHSHQWUXSDOLHUXOWDFWXOXLGH7

VHVSXQHF WDFWXO

DUHQLYHOXODFWLYVHQRWHD] FX7úLVHVLPEROL]HD] FX

•

'DF SRU LOHGHDFFHVVXQWYDOLGDWHSHQWUXSDOLHUXOWDFWXOXLGH7 DUH QLYHOXO DFWLY   VH QRWHD]  FX

VHVSXQHF WDFWXO

úLVHVLPEROL]HD] FX

Variante constructive In fig.8 sunt prezentate câteva variante de bistabile RS tip latch. 2EVHUYD LHVHUHPDUF IDSWXOF SRU LOHGHDFFHV6,DXQLYHOXODFWLYDOWDFWXOXLORJLFvQWLPSFH SRU LOHGHDFFHV6$8DXQLYHOXODFWLYDOWDFWXOXLORJLF

Fig.8. Variante constructive de bistabile RS tip latch &RQVLGHUD LLWLSXULOHGHVLQFURQLVPDOHELVWDELOHORU

8]XDOVHvQWkOQHVFXUP WRDUHOHWUHLWLSXULGHVLQFURQLVPDOHFLUFXLWHORUEDVFXODQWHELVWDELOH

Bistabil de tip latch (VWHWLSXOGHVLQFURQLVPFDUHDIRVW SUH]HQWDW vQ SDUDJUDIXO DQWHULRU,Q DFHVW FD] LQWU ULOH GH GDWH 56' VXQWvQ OHJ WXU FXELVWDELOXOHOHPHQWDULQWHUQXQ vQWUHJ LQWHUYDO GH WLPS FkWWDFWXO HVWH SH QLYHO DFWLY 8QXL DVWIHO GH VLQFURQLVP , VH PDL VSXQH VLQFURQ SH SDOLHUXO WDFWXOXL 6H UH LQH FRQYHQ LDFXSULYLUH OD QRWDUHDWDFWXOXLúL QLYHOXODFWLYDODFHVWXLD6H IDFH REVHUYD LD F  DFHVW WLS

de sincronism nu permite realizarea tuturor tipurilor de bistabile (de exemplu bistabil tip JK ). Bistabil sincron pe frontul impulsului de tact ,Q DFHVW FD] LQWU ULOH GH GDWH VXQW vQ OHJ WXU  FX ELVWDELOXO

exact numai pe durata unui front al

LPSXOVXOXL GH WDFW DGLF  XQ LQWHUYDO GH WLPS LQILQLW PLF ,Q PRPHQWXO IURQWXOXL DFWLY DO WDFWXOXL LHúLUHD 4 D ELVWDELOXOXL VH PRGLILF  FRQIRUP GDWHORU DIODWH OD LQWU ULOH GH GDWH 56 -. 7 '  vQ DFHOPRPHQW,QWUHGRX IURQWXULDFWLYHDOHWDFWXOXLLHúLUHDELVWDELOXOXLU PkQHQHPRGLILFDW 

&RQYHQ LH

•

'DF  IURQWXO DFWLY DO WDFWXOXL HVWH FHO FUHVF WRU LQWUDUHD GHWDFW VH QRWHD]  FX7 úL VH VLPEROL]HD] FX

•

'DF IURQWXODFWLYDOWDFWXOXLHVWHFHOGHVFUHVF WRULQWUDUHDGHWDFWVHQRWHD] FX úLVHVLPEROL]HD] FX

2EVHUYD LH

Evident un bistabil este activ pe un anumit front al tactului ("positive edge" sau "negative edge"). 'RX IURQWXULDFWLYHDOHWDFWXOXLVXQWVHSDUDWH GHR SHULRDG  D VHPQDOXOXL GUHSWXQJKLXODU GH WDFW 5H]XOW  F  LHúLUHD ELVWDELOXOXL VH PRGLILF  OD IURQWXO DFWLY DO VHPQDOXOXL GH WDFW úL U PkQH QHPRGLILFDW vQWUHDJDSHULRDG FDUHXUPHD] SkQ ODIURQWXODFWLYXUP WRU

Bistabil de tip "master-slave" &RQVWUXF LH ,Q SULQFLSLX XQ DVWIHO GH ELVWDELO HVWH FRPSXV GLQ GRX  ELVWDELOH GH WLS ODWFK OHJDWH vQ FDVFDG  XQXOSXUWkQGQXPHOHGHPDVWHUúLDOGRLOHDGHVODYH,QWU ULOHDQVDPEOXOXLPDVWHUVODYHFRLQFLGFX LQWU ULOHELVWDELOXOXLPDVWHULDULHúLULOHDQVDPEOXOXLFRLQFLGFXLHúLULOHELVWDELOXOXLVODYH )XQF LRQDUH (VHQ LDO vQIXQF LRQDUHDXQXLELVWDELOPDVWHUVODYHHVWHGHFDODUHDWDFWXOXLGLQWUHPDVWHUúLVODYH

, t2) datele de la intrare , t3 0DVWHUXOLQWU vQEORFDUHLDU6ODYHXO este în continuare blocat. Pe intervalul (t3, t4) Master-ul este blocat, în schimb Slave-ul îl copie pe Master (Slave-ul este de tip D de copiere). Pe (t4, t1) ambele sunt blocate ciclul repetându-se în

DVWIHOvQFkWDQVDPEOXOV IXQF LRQH]HvQGRLWLPSL$VWIHOvQLQWHUYDOXOW1 LQWU vQ0DVWHULDU6ODYHXOHVWHEORFDWÌQLQWHUYDOXOW2

FRQWLQXDUH 6HREVHUY  XQ FLFOX GH IXQF LRQDUH vQ GRL WLPSL ILHFDUH WDFW ILLQG IRUPDW GLQ SULPD SDUWHvQFDUHVHLQWU vQ0DVWHUúLGLQDGRXDSDUWHFkQGGDWHOHVHWUDQVIHU GLQ0DVWHUvQ6ODYH

Fig.9. Structura de principiu a unui bistabil tip Master-Slave

2EVHUYD LH

Intervalele (t2, t3  úL W4, t1) în care ambele bistabile sunt EORFDWH VLPXOWDQ SRW IL UHGXVH OD PLQLPXP FD GXUDW  IRUPD GH XQG  DU WkQG FD vQ ILJ DGLF  FHOH GRX IRUPHGHXQG VXQWFRPSOHPHQWDUH

Fig.10.Decalarea tactelor Concluzie 3HQWUX D UHDOL]D GHFDODMXO GLQWUH WDFWXO DSOLFDW OD 0DVWHU úL FHO DSOLFDWOD6ODYHILHF VHYRUIRORVL0DVWHUúL6ODYHGRX ODWFK XUL GH DFHODúL WLS úL DWXQFL VH IRORVHúWH XQ LQYHUVRU SHQWUX LQYHUVDUHD QLYHOXOXL DFWLY DO WDFWHORU vQWUH 0DVWHU úL 6ODYH YH]L ILJ  ILH 0DVWHUXO úL 6ODYHXO YRU IL FRQVWUXLWH FX SRU L GH DFFHVGHWLSGLIHULWXQXO6,FHO ODOW6$8 úLDWXQFLWDFWXOSRDWH

fi aplicat paralel (vezi exemplele ulterioare). Fig.11. Tact comun 2EVHUYD LH ,HúLUHD 4 D ELVWDELOXOXL 0DVWHU6ODYH VH PRGLILF  DWXQFL FkQG 6ODYH vQFHSH V O FRSLH SH 0DVWHU DGLF  vQ PRPHQWXO W3 ,Q FRQVHFLQ

 ELVWDELOXO 0DVWHU6ODYH YD IXQF LRQD DSDUHQW LGHQWLF FX XQ

ELVWDELOVLQFURQSHIURQWúLDQXPHFDúLFXPDUDYHDIURQWDFWLYIURQWXOFDUHEORFKHD] SH0DVWHUúL GHVFKLGH SH 6ODYH ,Q FRQVHFLQ

 VH DGRSW  R FRQYHQ LH GH QRWDUH VLPLODU  FHOHL DSOLFDW  OD

bistabilul sincron pe front : • 'DF DFFHVXOvQ0DVWHUHVWHSHUPLVSHQWUX7DFW

úLDFFHVXOvQ6ODYHSHQWUX7DFW

DWXQFL

LHúLUHD VH PRGLILF  OD IURQWXO FUHVF WRU DO WDFWXOXL LQWUDUHD GH WDFW VH QRWHD]  FX 7 úL VH VLPEROL]HD] FX

•

'DF DFFHVXOvQ0DVWHUHVWHSHUPLVSHQWUX7DFW LQWUDUHDGHWDFWVHQRWHD] FX

úLDFFHVXOvQ6ODYHSHQWUX7DFW

úLVHVLPEROL]HD] FX

DWXQFL

7LSXULGHELVWDELOHLQWHJUDWHVLQFURQHUHSUH]HQWDUHWDEHOHGHDGHY UHFXD LL

Bistabilul sincron de tip RS Reprezentare

Tactul poate fi :

• latch • front (edge) • Master-Slave

9RPQRWDFX+YDULDELODFDUHGHILQHúWHWDFWXOLQGLIHUHQWGHWLSXOV X úLIDFHPFRQYHQ LD

H = 1 pentru tact activ H = 0 pentru tact inactiv (FXD LH

Qn+1 = H n ⋅ Qn + H n ( S n + Rn ⋅ Qn )

Bistabilul de tip JK Reprezentare

Tactul poate fi :

• edge • Master-Slave

,QFD]XOELVWDELOXOXL-.WDFWXOQXSRDWHILGHWLS ODWFKGHRDUHFHSHQWUXFRPELQD LD-

.

úLWDFWXO

DFWLY LHúLUHD 4 DU WUHFH vQ RSXV úL DSRL GLQ QRX vQ RSXV úL DúD PDL GHSDUWH DGLF  vQ GHILQLWLY DU

oscila tot timpul cât tactul este activ. (FXD LH

Q n +1 = H n ⋅ Q n + H n (J n ⋅ Q n + K n ⋅ Q n )

2EVHUYD LH %LVWDELOXO -. DUH DFHHDúL IXQF LRQDUH FX FHD D ELVWDELOXOXL 56 FX GHRVHELUHD F  DFROR XQGH ELVWDELOXO 56  DUH QHGHWHUPLQDUH SHQWUX 5 GHWHUPLQDW SHQWUX-

.

6

   ELVWDELOXO -.  DUH R IXQF LRQDUH SHUIHFW

ODDSOLFDUHDWDFWXOXLELVWDELOXOWUHFHvQVWDUHDRSXV 

Din acest punct de vedere, bistabilul JK poate fi considerat un fel de generalizare a bistabilului 56vQVHQVXOF IXQF LRQHD] LGHQWLFFXDFHVWDúLvQSOXVUH]ROY úLQHGHWHUPLQDUHDVD

Bistabilul de tip D Denumirea D provine de la D = delay (întârziere). Bistabilul D este un bistabil de copiereDGDWHORUGDWDGHODLQWUDUHD'HVWHFRSLDW

ODLHúLUHD4vQ

PRPHQWXO DSOLF ULL WDFWXOXL 8Q DVWIHO GH ELVWDELO QLFL QX SRDWH IL FRQFHSXW vQWUR IXQF LRQDUH DVLQFURQ I U WDFW 

Reprezentare:

Tactul poate fi :

• latch • edge • Master-Slave

(FXD LH

Q n +1 = H n ⋅ Q n + H n ⋅ D n

Bistabilul de tip T Denumirea provine de la T = toggle (basculare). A nu se confunda T de la toggle cu T de la tact. Reprezentare

Tactul poate fi :

• edge • Master-Slave

(FXD LH

Qn+1 = H n ⋅ Qn + H n (Tn ⊕ Qn ) &DúLELVWDELOXO-.ELVWDELOXOGHWLS7QXDFFHSW WDFWGHWLSSDOLHUGHRDUHFHSHQWUX7

DURVFLOD

5. Transformarea unui tip de bistabil în alt tip de bistabil Dispunem de un tip de bistabil, fie el X∈^-. ' 7 56` úL GRULP V bistabil de alt tip, Y∈{JK, D, T, RS}.

O WUDQVIRUP P vQWUXQ

3UREOHPD VH UH]ROY  DVWIHO VH DGDXJ  XQ &/& &LUFXLW /RJLF &RPELQD LRQDO  vQ ID D ELVWDELOXOXL ;SHQWUXDOWUDQVIRUPDvQ<úLVHDSOLF UHDF LHGHODLHúLUHD4 3HQWUX D GHWHUPLQD VWUXFWXUD &/&XOXL VH SURFHGHD]

astfel: • VH VFULH WDEHOXO GH DGHY

U SHQWUX ELVWDELOXO < FH VH

GRUHúWH D VH RE LQH DYkQG JULM  V  VH FRPSOHWH]H úL

coloanele QnúL4n+1. • VH FRPSOHWHD]  DSRL DFHVW WDEHO FX R QRX

 FRORDQ

XWLOL]kQGWDEHOXOGHVW ULDOELVWDELOXOXL;FDUHV DVLJXUHWUHFHULOHFRUHVSXQ] WRDUH

•

6HGHWHUPLQ DSRLIXQF LDORJLF ;

I<4n FDUHVHPLQLPL]HD] 

2EVHUYD LH (YLGHQWWDFWXO + GH OD ELVWDELOXO GH SOHFDUH ; VH S VWUHD]  úL OD ELVWDELOXO RE LQXW <

(vezi compatibilitatea tactelor). Exemplul 16

VHWUDQVIRUPHELVWDELOXO56vQELVWDELO-. &RQIRUP

QRWD LLORU

REVHUY F ;

56úL<

DQWHULRDUH

VH

-.

6HDSOLF PHWRGDGHVFULV PDLVXVúLVH RE LQHFXD LLOHFDUHGHVFULX&/&XO

R = K ⋅ Qn úL S = J ⋅ Qn Schema de transformare a bistabilului 56 vQ -. LPSOHPHQWHD]  FHOH GRX HFXD LLúLHVWHUHSUH]HQWDW vQILJXU 

Evident tactul bistabilului de plecare RS poate fi numai de tip edge sau M-S DúDFXPFHUHELVWDELOXO-.

Fig.12. Transformarea unui bistabil RS în bistabil JK Exemplul 26

VHWUDQVIRUPHXQELVWDELO56vQELVWDELO'

Fig.13. Transformarea unui bistabil de tip RS (JK) în bistabil de tip D 6HDSOLF PHWRGDDQWHULRDU úLVHVWDELOHVFHFXD LLOH6

2EVHUYD LH

'úL

R = D.

7UDQVIRUPDUHD ELVWDELOXOXL GH WLS -. vQ ' HVWH LGHQWLF  FX FHD D ELVWDELOXOXL GH WLS 56 ELVWDELOXO

D este un bistabil de copiere).

1X H[LVW  SUREOHPH GH FRPSDWLELOLWDWH D WDFWXOXL GHRDUHFH ELVWDELOXO GH WLS ' SRDWH DGPLWH WRDWH

tipurile de tact. (VWHSRVLELOFDGDWHOHFHVHGRUHVFDILFRSLDWHGHELVWDELOXO'V SURYLQ GHODXQELVWDELODQWHULRU FDUH DUH LHúLUL DWkW 4 FkW úL FRPSOHPHQWDUXO DFHVWXLD ,Q DFHVW FD] VH YD REVHUYD LGHQWLWDWHD IXQF LRQDO GLQWUHXUP WRDUHOHWUHLVFKHPH

)LJ&RQHFWDUHDvQFDVFDG DPDLPXOWRUELVWDELOHGHWLS' 6H REVHUY  F  vQ XOWLPD YDULDQW  QX PDL QHFHVDU XQ LQYHUVRU vQWUH 5 úL 6 GHRDUHFH ELVWDELOXO DQWHULRUDUHGLVSRQLELO DWkWLHúLUHD4FkWúLLHúLUHD4 

3UREOHP 6HSRUQHúWHGHODXQ-.56'VDX76 VHRE LQ XQELVWDELOFXLQWU ULQRWDWH $%&FDUHV IXQF LRQH]HDVWIHO

- pentru A = 0 ⇒LQWU ULOH%úL&V IXQF LRQH]HVLPLODUFX-.DGLF %∼J, C∼K - pentru A=1, B=0 ⇒LQWUDUHD&V IXQF LRQH]HVLPLODULQWU ULL'DGLF &∼D - pentru A=1, B=1 ⇒LQWUDUHD&V IXQF LRQH]HVLPLODULQWU ULL7DGLF &∼T 6. Exemple de circuite basculante bistabile integrate 6.1. Circuitul TTL 475 (D latch) 5HFXQRDúWHP ELVWDELOXO HOHPHQWDU UHDOL]DW FX SRU LOH   úLSRU LOH GH DFFHV    GHFL FLUFXLWXO FRQVWUXLW FX SRU LOH  IRUPHD]  XQ ODWFK GH WLS 56 LQYHUVRUXO  WUDQVIRUP

RS-ul în D.

Fig. 15. Circuitul TTL 475

6.2.CBB de tip Master-Slave de tip RS cu inversor pe tact 6HYDSUH]HQWDXQFLUFXLW EDVFXODQW ELVWDELO WLS 56 0DVWHU6ODYH SUHY ]XW VXSOLPHQWDU FX LQWU UL

asincrone, prioritare RA SA active pe nivel 0. 6FKHPDHOHFWULF HVWHSUH]HQWDW vQILJ

&RQVWUXF LH 5HFXQRDúWHP R VWUXFWXU  0DVWHU6ODYH vQ FDUH 0DVWHU HVWH UHDOL]DW FX SRU LOH  GLQ FDUH   IRUPHD]  ELVWDELOXO HOHPHQWDU LDU  VXQW SRU L GH DFFHV ELVWDELOXO 6ODYH HVWH UHDOL]DW FX SRU LOH GLQWUHFDUHIRUPHD] XQELVWDELOHOHPHQWDULDUVXQWSRU LGHDFFHV ÌQWUXFkW SRU LOH GH DFFHV  UHVSHFWLY  VXQW GH DFHODúL WLS WDFWXO FHORU GRX  ODWFKXUL HVWH

decalat de inversorul 9.

)LJ&%%WLS560DVWHU6ODYHSUHY ]XWFXLQWU ULSULRULWDUHGH6HWúL5HVHW

6HREVHUY F 6ODYHXOHVWHGHWLS56DUH6OHJDWODLHúLUHD4GHOD0DVWHUúL5OHJDWODLHúLUHD4¶ GHOD0DVWHUDGLF 6ODYHFRSLHSH0DVWHUHYLGHQWDWXQFLFkQGvLSHUPLWHWDFWXO 

)XQF LRQDUH ,QWDEHOXOGHDGHY UVHGHVFULH IXQF LRQDUHDFLUFXLWXOXLúLGLQDQDOL]DDFHVWXLDUH]XOW 

-

LQWU ULOH

R A , SA

 VXQW SULRULWDUH DVLQFURQH úL DX QLYHOXO DFWLY  ORJLF YH]L SULPHOH 

UkQGXULGLQWDEHOXOGHDGHY U

-

vQUHVWXOWDEHOXOXLGDF  LQWU ULOHSULRULWDUHVXQWLQDFWLYHWDEHOXO QHDUDW R IXQF LRQDUH FODVLF GHELVWDELO560DVWHU6ODYH

)XQF LRQDUHDSHLQWU ULOHDVLQFURQH

(primele trei rânduri ale tabelului):

9RPXUP ULIDSWXOF DFHVWHLQWU ULVXQWDFWLYHSHúLVXQWSULRULWDUHDGLF GDF FHOSX LQXQDGLQ HOHHVWHDFWLYDW FLUFXLWXODVFXOW GHDFHDVWD 

Fie R A = 0, S A = 0 SULPXOUkQGGLQWDEHOVHREVHUY GHWHUPLQ 4

4 

LQGLIHUHQWGHVWDUHDFHORUODOWHLQWU UL

Fie R A = 0, S A = 1   OLQLD GRL GLQ WDEHOXO GH DGHY 7DFW

F FHOH GRX  LQWU UL DSOLFDWH GLUHFW SRU LORU

U YRP FRQVLGHUD GLVWLQFW FD]XULOH  7DFW

 úL YRP REVHUYD F  RULFDUH DU IL WDFWXO  LHúLULOH VXQW FRQIRUP WDEHOXOXL 4

  úL 4 

 úL  

LQGLIHUHQWGHLQWU ULOH5úL6

a. ILH 7DFW

  DFHVWD GHWHUPLQ  SRDUWD 39

 úL LPSOLFLW SRU LOH  35

SRU LORUúLVHDSOLF HOHPHQWQHXWUX úLLQWU ULOH 2EVHUYD LH,QWU ULOH 4¶

R A , SA

R A = 0, S A = 1 5H]XOW

=P6 4

  OD LQWU ULOH 4¶



VHDSOLF úL 0DVWHUXOXL  DúH]kQGXO úL SH DFHVWD vQ VWDUHD 4

 

FDúL6ODYHXOGHúLSRU LOHúLILLQGEORFDWHQXODV OHJ WXU vQWUH0DVWHUúL6ODYH

b. ILH 7DFW

 FHHD FH GHWHUPLQ  31

DFFHVXOvQ0DVWHUSHGHDOW SDUWH39

= P2

  LQGLIHUHQW GH LQWU ULOH 5 úL 6  EORFKHD]

YDOLGHD] SRU LOHGHDFFHVúLÌQFRQVHFLQ

este conectat la intrarea Slave-ului. ,QWU ULOH R A = 0, S A = 1  VH DSOLF  VLPXOWDQ DWkW 0DVWHUXOXL FkW úL 6ODYHXOXL QM  4úL4¶M  4¶DFHHDúLVWDUHDWkWSHQWUX0DVWHUFkWúLSHQWUX6ODYH

0DVWHUXO

úL GHWHUPLQ

6H REVHUY  F  vQ DFHDVW  VLWXD LH HVWH QHFHVDU  FRQWURODUHD 0DVWHUXOXL VLPXOWDQ FX D 6ODYHXOXL SHQWUXFDQXFXPYDODELVWDELOXOHOHPHQWDUV DMXQJ RFRPDQG QHSHUPLV GHWLS 

,Q FRQFOX]LH  YH]L SFW D úL E  VH FRQVWDW  F  LQGLIHUHQW GH WDFW FRPDQGD GHWHUPLQDWWUHFHUHDELVWDELOXOXL vQ VWDUHD4

4¶

R A = 0, S A = 1 a

FXDWkWPDL PXOW LQGLIHUHQWGHLQWU ULOH5úL

6 GHWHUPLQkQGúLWUHFHUHDELVWDELOXOXL0DVWHUvQDFHHDúLVWDUH

6LPLODUVH XUP UHúWH OLQLD  GLQ WDEHOXO GH DGHY U SHQWUX FDUH FRPDQGD WUHFHUHDELVWDELOXOXLvQVWDUHD4

úL4 

R A = 1, S A = 0 GHWHUPLQ



)XQF LRQDUHDSHLQWU ULOHVLQFURQH5úL6 ,Q DFHVW FD] LQWU ULOH DVLQFURQH VXQW LQDFWLYH DGLF 

R A = S A = 1 ; 1 fiind element neutru pentru

RSHUD LLOHù,SXUúLVLPSOXSXWHPIDFHDEVWUDF LHGHLQWU ULOH

R A , SA .

&HHD FH U PkQH HVWH R FDVFDG  GH WLS 0DVWHU6ODYH FX SRU L 6,18 SHQWUX 7DFW LQWU ULOH 56 LQWU  vQ 0DVWHU 6ODYH ILLQG EORFDW SHQWUX 7DFW



 GDWHOH GH OD

⇒ 0DVWHU HVWH EORFDW úL 6ODYH

validat copiindu-l pe Master. 5H]XOW  R IXQF LRQDUH FODVLF  GH ELVWDELO 0DVWHU6ODYH vQ FDUH DSDUHQW FLUFXLWXO IXQF LRQHD]  FD XQELVWDELODFWLYSHIURQWGHVFUHVF WRUDOWDFWXOXL

Transformarea în bistabil JK :

%LVWDELOXO 56 SRDWH IL WUDQVIRUPDW vQ -. DG XJkQGXL

ELQHFXQRVFXWHOHUHDF LLGHGXVHvQWUXQSDUDJUDIDQWHULRUVHREVHUY F WDFWXOGHWLS0DVWHU6ODYH HVWH FRPSDWLELO DWkW FX ELVWDELOXO 56 FkW úL FX FHO -.   5HDF LLOH GH OD LHúLUH QX QHFHVLW  SRU L VXSOLPHQWDUH DSOLFkQGXVH GLUHFW SRU LORU úL  IRVWD LQWUDUH 6 GHYHQLQG - LDU IRVWD LQWUDUH 5 GHYHQLQG.'XS WUDQVIRUPDUHVHRE LQHXQELVWDELOWLS-.0DVWHU6ODYHFXLQWU UL56SULRULWDUH úLDFWLYHSHQLYHO

Fig. 17 Transformarea bistabilului RS în bistabil JK

1RXOELVWDELODUH LQWU ULOH SULRULWDUH

FDUH

R A , SA

IXQF LRQHD] 

bistabilul analizat mai sus RS.

 DVLQFURQH úL

LGHQWLF

FD

OD

6.3. CBB de tip Master-Slave RS cu tact paralel %LVWDELOXODUHVFKHPDúLWDEHOXOGHDGHY UGLQILJXU 

Fig.18. CBB tip RS, Master-Slave cu tact paralel

&RQVWUXF LH 6HREVHUY  FRQVWUXF LD GH WLS 0DVWHU6ODYH 0DVWHU SRU LOH  6ODYH  SRU LOH   VH REVHUY SRU LOHGHDFFHVFDUHVXQWù,LDUSRU LOHGHDFFHVFDUHVXQW6$8

deci tactul latch-urilor

QX PDL WUHEXLH LQYHUVDW FL VH DSOLF  SDUDOHO 6H UHPDUF  FRQVWUXFWLY F  LQWU ULOH DVLQFURQH

R A , SA

 VXQW DSOLFDWH DWkW OD 0DVWHU FkW úL OD 6ODYH GDU FDUH QHFHVLW  VXSOLPHQWDU SRU LOH  úL

FRQHFWDUHDFRQYHQDELO SHQWUXDDVLJXUDFRPSDWLELOLWDWHD )XQF LRQDUHD &LUFXLWXOIXQF LRQHD] LGHQWLFFXFHOGLQ FD]XO DQWHULRU7UDQVIRUPDUHD56 vQ-. vQDFHVWFD]HVWH LGHQWLF FDvQFD]XODQWHULRUSULQUHDF LLOHGHODLHúLULODSRU LOHúL

%LVWDELOHOH 77/   úL  VXQW ELVWDELOH -. 0DVWHU6ODYH FDUH SURYLQ GLQ ELVWDELOH 56 FX WDFW SDUDOHO DYkQG R FRQVWUXF LH DVHP Q WRDUH  ELVWDELOXO  0DVWHU HVWH XQ ODWFK FRQVWUXLW FX SRU L GH DFFHV GH WLS 6, LDU ELVWDELOXO HOHPHQWDU FX SRU L 6$818 vQ WLPS FH ELVWDELOXO 6ODYH HVWH XQ ODWFK FRQVWUXLW FX SRU L GH DFFHV 6$8 LDU ELVWDELOXO HOHPHQWDU HVWH FX 6,18 6XQW SUHY ]XWH FX LQWU ULDVLQFURQHSULRULWDUHLGHQWLFHFXFHOHDQDOL]DWHPDLVXV

6.4. Circuite basculante bistabile CMOS ([LVWHQ D SRU LORU GH WUDQVPLVLH SHUPLWH FD vQ IDPLOLD &026 V  ILH UHDOL]DWH ELVWDELOH DYkQG R VWUXFWXU  FKLDU PDL VLPSO  GHFkW FHD DQDOL]DW  OD FLUFXLWHOH DQWHULRDUH 5HDPLQWLP F  R SRDUW  GH WUDQVPLVLH&026HVWHIRUPDW GLQGRX WUDQ]LVWRDUH026XQXOFXFDQDOLQGXVGHWLSSúLXQXOFX FDQDO LQGXV GH WLS Q FRQHFWDWH vQ SDUDOHO úL FRPDQGDWH VLPXOWDQ GH GRX  VHPQDOH GH FORFN FRPSOHPHQWDUH DVWIHO vQFkW RUL DPEHOH VXQW EORFDWH RUL DPEHOH VXQW GHFKLVH 3RDUWD DVLJXU FRQGXF LHELGLUHF LRQDO 

/DWFKGHWLS'vQFRQVWUXF LH&026

6FKHPDHOHFWULF DXQXLDVWIHOFLUFXLWHVWHSUH]HQWDW vQILJ

Fig.19. Latch CMOS de tip D &RQVWUXF LH 3RU LOH  úL  SHUPLW RE LQHUHD FHORU GRX  FORFNXUL FRPSOHPHQWDUH QHFHVDUH SHQWUX FRPDQGD SRU LORUGHWUDQVPLVLH 6H UHPDUF  GH DVHPHQHD IDSWXO F  SRU LOH GH WUDQVPLVLH 371 úL 372 VXQW FRPDQGDWH GH DFHODúL FORFNvQRSR]L LHFkQGXQDHVWHGHVFKLV FHDODOW HVWHEORFDW úLLQYHUV 

)XQF LRQDUH &LUFXLWXOIXQF LRQHD] GXS FXPXUPHD] 

• Pentru CL = 1 ⇒ CL = 0

úL FD XUPDUH 371 HVWH GHVFKLV  úL 372 EORFDW  ÌQ DFHVW FD]

FLUFXLWXOHFKLYDOHQWHVWHGHIRUPDFHOXLGLQILJDLHúLUHD4XUP ULQGILGHOLQWUDHD'

• Pentru CL = 0 ⇒ CL = 0 úLSRDUWDGHWUDQVPLVLH371HVWHEORFDW

LDU372GHVFKLV ÌQ

DFHVW FD] FLUFXLWXO HFKLYDOHQW HVWH FHO GLQ ILJE SRU LOH  úL  OXkQG VWUXFWXUD  XQ ELVWDELO HOHPHQWDUúLPHPRUkQGGDWDFDUHDIRVWDQWHULRUODLQWUDUHD'

)LJ)XQF LRQDUHDELVWDELOXOXLODWFKGHWLS'

Concluzii %LVWDELOXOSUH]HQWDWDUHRIXQF LRQDUHFODVLF GHFLUFXLWODWFKSRDUWDGHWUDQVPLVLH371

jucând

UROXOXQHLSRU LGHDFFHVLDUSRU LOHúL372ILLQGELVWDELOXOHOHPHQWDU,QFRQVWUXF LH&026 ELVWDELOXOWLS'HVWHFHOFDUHVW ODED]DUHDOL] ULLFHORUODOWHWLSXULGHELVWDELOH

,QVHULD&026H[LVW FLUFXLWXOFDUHDUHH[DFWVFKHPDDQDOL]DW DYkQGvQSOXVvQF R LQWUDUHSULQFDUHVHSRDWHVWDELOLQLYHOXODFWLYDOWDFWXOXLvQIDSWLQWHUFDOHD] VDXQXVXSOLPHQWDUvQ VHULHFXSRU LOHúLvQF RSRDUW LQYHUVRDUH 

6.4.2

%LVWDELOGHWLS'0DVWHU6ODYHvQFRQVWUXF LH&026

'HVLJXU F  úL vQ FRQVWUXF LH &026 SRW IL UHDOL]DWH FLUFXLWH FX SRU L vQ YDULDQWHOH 0DVWHU6ODYH FDUHDXIRVWSUH]HQWDWHDQWHULRU6HSRWvQV UHDOL]DúLDOWIHOGHFLUFXLWHGHH[HPSOXFHOGLQILJ

)LJ%LVWDELOWLS'0DVWHU6ODYHvQFRQVWUXF LH&026

&RQVWUXF LH 6HUHFXQRDúWHRFRQVWUXF LH0DVWHU6ODYHvQFDUHFHOHGRX ODWFKXULVXQWGHIDSWLGHQWLFHFXFHO GLQILJVLQJXUDPRGLILFDUHILLQGWUDQVIRUPDUHDSRU LORU18127 vQSRU L6,181$1' FX VFRSXOGHDVHSXWHDDSOLFDLQWU ULOHGHIRU DUHDVLQFURQH5úL6 &LUFXLWXO 0DVWHUHVWHUHDOL]DWFXSRU LOHGHWUDQVPLVLH371 6ODYHHVWHUHDOL]DWFXSRU LOHGHWUDQVPLVLH373

, PT2úLSRU LOH ORJLFH  úL  %LVWDELOXO

, PT4úLSRU LOHORJLFHúL

bufferare.

3RU LOHúLDXUROGH

3RU LOHúLSHUPLWRE LQHUHDDGRX WDFWHFRPSOHPHQWDUHQHFHVDUHSHQWUXFRPDQGDSRU LORUGH

transmisie. 6HUHPDUF IDSWXOF 371úL372VXQWFRPDQGDWHvQRSR]L LHDúDFXPHVWHQHFHVDUODXQODWFK 'H DVHPHQHDSRU LOH373úL374VXQWFRPDQGDWHvQRSR]L LH 6HREVHUY GHDVHPHQHDIDSWXOF SRU LOHGHDFFHVvQ0DVWHUúLvQ6ODYH371úLUHVSHFWLY373

sunt

FRPDQGDWHvQRSR]L LHDúDFXPHVWHQHFHVDUODXQDQVDPEOX0DVWHU6ODYH

)XQF LRQDUH )XQF LRQDUHDELVDWELOXOXLHVWHGHVFULV GHWDEHOXODO WXUDW

6HREVHUY F LQWU ULOHDVLQFURQH56VXQWSULRULWDUHVH DSOLF GLUHFWELVWDELOHORUHOHPHQWDUHFXQLYHODFWLY  $WXQFLFkQG56VXQWLQDFWLYHELVWDELOHOHIXQF LRQHD] FXLQWU ULOH'úL&/GXS SULQFLSLXOFODVLFDOELVWDELOHORU

master-slave. $QDOL]D IXQF LRQ ULL FLUFXLWXOXL VH SRDWH IDFH LPHGLDW IRORVLQG GUHSW PRGHO FHOHODOWH ELVWDELOH GH

tip Master-Slave analizate în capitolele anterioare.

2EVHUYD LH 'XS  FXP DX IRVW SUH]HQWDWH ELVWDELOHOH vQ FRQVWUXF LH &026 FHO PDL VLPSOX VH UHDOL]HD] ELVWDELOHOHGHWLS ' FRPSDUDWLY FX FHOH GH WLS 56 $WXQFL FkQG VH GRUHúWH UHDOL]DUHD XQXL ELVWDELO -. VDX 7  vQ YDULDQW  &026 VH SRUQHúWH GH OD XQ ELVWDELO GH WLS ' FDUH XOWHULRU VHWUDQVIRUP  vQ

JK sau T. In seria 4000 sunt realizate circuitul 4013, bistabil de tip D Master-Slave exact cu schema DQDOL]DW  PDL VXV úL ELVWDELOXO  FDUH HVWH XQ ELVWDELO GH WLS -. 0DVWHU6ODYH RE LQXW SULQ

transformarea bistabilului D în bistabil JK. 7. Regimul dinamic al circuitelor basculante bistabile 7LPSLLVSHFLILFLFDUHFDUDFWHUL]HD] IXQF LRQDUHDELVWDELOHORUVXQW

-

WLPSGHSURSDJDUHGHODLQWUDUHODLHúLHWp GXUDWDPLQLP DLPSXOVXOXLDFWLYGHODLQWUDUHWw WLPSLGHUH]HUY LQDLQWHDúLGXS IURQWXODFWLYDOWDFWXOXL

'HWDOLD LSHQWUXILHFDUHWLSGHELVWDELODFHúWLDVXQWSUH]HQWD LPDLMRV

%LVWDELODVLQFURQELVWDELOHOHPHQWDUWLS56VDXLQWU ULSULRULWDUHODXQELVWDELO0DVWHU6ODYH

In conformitate cu fig.22 se definesc XUP WRULLSDUDPHWULL

twGXUDWD PLQLP

 D QLYHOXOXL

DFWLY DO LQWU ULL DVLQFURQH QLYHOXO

activ poate fi L sau H. tp In-Q - timp de propagare de OD LQWUDUH OD LHúLUHD 4  HVWH WLPSXO VFXUV vQWUH PRPHQWXO DSOLF ULL XQHL FRPHQ]L OD LQWUDUH úL PRPHQWXO vQ FDUHLHúLUHDH[HFXW DFHDFRPDQG 

Fig.22. Timpii specifici unui bistabil asincron Exemple : &LUFXLWXO

• •

%LVWDELOWLS0DVWHU6ODYHVHULD77/VWDQGDUGFRPHQ]LSHLQWU ULOHDVLQFURQH

tw(L) = 25 ns tp R,S-Q = QVSHQWUXYDULD

LDLHúLULL/+

QVSHQWUXYDULD LDLHúLULL+/

&LUFXLWXO

• •

%LVWDELO'0DVWHU6ODYHVHULD&026FRPHQ]LSHLQWU ULOHDVLQFURQH

tw(H) =

25 ns pentru VDD = 5 V 12 ns pentru VDD = 10 V 10 ns pentru VDD = 15 V tp R,S - Q = 60 ns pentru VDD 9YDULD LD/+ 30 ns pentru VDD 9YDULD LD/+ 20 ns pentru VDD 9YDULD LD/+

100 ns pentru VDD 9YDULD LD+/ 40 ns pentru VDD 9YDULD LD+/ 30 ns pentru VDD 9YDULD LD+/

Bistabil sincron de tip latch

)LJ7LPSLLVSHFLILFLIXQF LRQ ULLXQXLELVWDELOGHWLSODWFK

• • •

tw 7

GXUDWDPLQLP DQLYHOXOXLDFWLYDOWDFWXOXL SHULRDGDPLQLP IUHFYHQ DPD[LP  DVHPQDOXOXLGHWDFW

tp CL-Q

 GXUDWD VFXUV  vQWUH PRPHQWXO IURQWXOXL GH vQFHSXW DO WDFWXOXL DFWLY úL PRPHQWXO vQ

FDUHLHúLUHDVHPRGLILF

•

tp D-Q

GXUDWDVFXUV vQWUHPRPHQWXO PRGLILF ULLXQHLGH OD LQWUDUHvQ LQWHULRUXO LQWHUYDOXOXL

vQFDUHWDFWXOHVWHDFWLY úLPRPHQWXOvQFDUHLHúLUHDVHPRGLILF

•

tsu = timp de prestabilire ( time set-up) = intervalul de timp de înaintea frontului de închidere DOWDFWXOXLvQFDUHGDWHOHGHODLQWU ULQXDXYRLHV VHPRGLILFH

•

th

WLPSGHPHQ LQHUWLPH KROG 

LQWHUYDOXOGHWLPSGHGXS IURQWXOGH vQFKLGHUHDOWDFWXOXL

vQFDUHGDWHOHGHODLQWU ULQXDXYRLHV VHPRGLILFH

Pe intervalul timpilor tsu + thHVWHLQWHU]LVDVHPRGLILFDGDWHOHGHODLQWU

ULLHúLUHD4SXWkQGDYHD

RIXQF LRQDUHGHIHFWXRDV vQFD]FRQWUDU

Exemple: Circuitul 475 = Bistabil tip D latch, seria TTL standard. • tsu = 20 ns • th = 5 ns • tp D-Q QVSHQWUXYDULD LD/+QVSHQWUXYDULD LD+/ • tp CL-Q QVSHQWUXYDULD LD/+QVSHQWUXYDULD LD+/ Bistabil sincron de tip Master-Slave $SDUHQWXQELVWDELO0DVWHU6ODYHDF LRQHD] VLPLODUXQXLELVWDELOVLQFURQGHWLSIURQWúLvQ FRQVHFLQ

WLPSLLVSHFLILFLVXQWGHILQL LVLPLODUILJ

)LJ7LPSLLVSHFLILFLIXQF LRQ ULLXQXLELVWDELOGHWLS0DVWHU6ODYH

• • •

tw   GXUDWD PLQLP Slave) ale tactului. 7

 SHQWUX FHOH GRX  QLYHOH DFWLYH XQXO SHQWUX 0DVWHU úL FHO ODOW SHQWUX

SHULRDGDPLQLP IUHFYHQ DPD[LP  DVHPQDOXOXLGHWDFW

tp CL-Q

GXUDWDVFXUV vQWUHPRPHQWXOIURQWXOXLDFWLYDOWDFWXOXLúLPRPHQWXO vQFDUH LHúLUHDVH

PRGLILF 

•

tsu = timp de prestabilire ( time set-up) = intervalul de timp de înaintea frontului activ al WDFWXOXLvQFDUHGDWHOHGHODLQWU ULQXDXYRLHV VHPRGLILFH

•

th

WLPSGHPHQ LQHUWLPHKROG 

LQWHUYDOXOGHWLPSGHGXS IURQWXODFWLYDOWDFWXOXL vQ FDUH

GDWHOHGHODLQWU ULQXDXYRLHV VHPRGLILFH

Pe intervalul timpilor tsu + thHVWHLQWHU]LVDVHPRGLILFDGDWHOHGHODLQWU

ULLHúLUHD4SXWkQGDYHD

RIXQF LRQDUHGHIHFWXRDV vQFD]FRQWUDU

Exemple: Circuitul 472 = Bistabil tip JK, Master-Slave, seria TTL standard. • tsu = 0 ns • th = 0 ns • tp CL-Q QVSHQWUXYDULD LD/+DLHúLULLQVSHQWUXYDULD LD+/DLHúLULL • tw (H) = 20 ns • tw (L) = 47 ns • fmax 0+]IUHFYHQ DPD[LP DWDFWXOXL Circuitul 4013 = Bistabil D, Master-Slave seria CMOS • tsu = 20 ns pentru VDD = 5 V; 10 ns pentru VDD = 10 V; 5 ns pentru VDD = 15 V • th = 0 • tp CL - Q = 95 ns pentru VDD 9YDULD LD/+ 110 ns pentru VDD 9YDULD LD+/ 40 ns pentru VDD 9YDULD LD/+ 45 ns pentru VDD 9YDULD LD+/ 30 ns pentru VDD 9YDULD LD/+ 30 ns pentru VDD 9YDULD LD+/ • fmax = 14 MHz pentru VDD = 5 V ; 28 MHz pentru VDD = 10 V ; 40 MHz pantru VDD = 15 V

Bistabil sincron pe frontul impulsului de tact

)LJ7LPSLLVSHFLILFLIXQF LRQ ULLXQXLELVWDELOVLQFURQSHIURQWXOWDFWXOXL

• • •

tw 7

GXUDWDPLQLP DQLYHOXOXLWDFWXOXLGLVWLQFW SHQWUXFHOHGRX QLYHOH  SHULRDGDPLQLP IUHFYHQ DPD[LP  DVHPQDOXOXLGHWDFW

tp CL-Q

GXUDWDVFXUV vQWUHPRPHQWXOIURQWXOXLDFWLYDOWDFWXOXLúLPRPHQWXO vQFDUH LHúLUHDVH

PRGLILF

•

tsu = timp de prestabilire ( time set-up) = intervalul de timp de înaintea frontului activ al WDFWXOXLvQFDUHGDWHOHGHODLQWU ULQXDXYRLHV VHPRGLILFH

•

th

WLPSGHPHQ LQHUWLPHKROG 

LQWHUYDOXOGHWLPSGHGXS IURQWXODFWLYDOWDFWXOXL vQ FDUH

GDWHOHGHODLQWU ULQXDXYRLHV VHPRGLILFH

Pe intervalul timpilor tsu + thHVWHLQWHU]LVDVHPRGLILFDGDWHOHGHODLQWU

ULLHúLUHD4SXWkQGDYHD

RIXQF LRQDUHGHIHFWXRDV vQFD]FRQWUDU 3HQWUXELVWDELOHOHVLQFURQHSH IURQWXO WDFWXOXL HVWH UHFRPDQGDELO FD IURQWXO DFWLY DO WDFWXOXL V  ILH SHFkWVHSRDWHPDLDSURDSHGHLGHDOGXUDW PLF úLI U RVFLOD LL

Exemple: &LUFXLWXO

• • • • • •

%LVWDELOWLS'VLQFURQSHIURQWXOFUHVF WRUDOWDFWXOXLVHULD77/VWDQGDUG

tsu = 20 ns th = 5 ns tp CL-Q QVSHQWUXYDULD LD/+DLHúLULLQVSHQWUXYDULD LD+/DLHúLULL tw (H) = 30 ns tw (L) = 37 ns fmax 0+]IUHFYHQ DPD[LP DWDFWXOXL