ISO_5V_A SHORT SPARK ISO_GND
7 8 9
C11
R2
ISO_5V_B 1.0 kΩ
ISO_5V_C TRIGGER
ISO_5V_D SHORT
THRESHOLD
SPARK +
C10 1 nF
DISCHARGE
10 nF OUTPUT
CONTROL
Compares Vcap to integrated PWM level to control charging
−
1 MΩ
−
1/4 LM324
R17
+
PS2501-4 ISO_5V_B CHARGE_EN
D3
U3-2 R15 30.1 kΩ
+
1 MΩ R16 1 kΩ
+
C8 3000 pF
+15V
U4-2
1/4 LM324
1%
+15V
C9
U3-3
D5 High-Lo Side Driver VCC
10 nF
XXX
In-rush current limiting
−
+15V
HIN
D4
1/4 LM324
R18 50 kΩ
+
Explicit Boost Enable
−
D10
+
Single Channel Driver VCC VB
10 nF
XXX
IN
IN +
C1 2200 uF
+
100 uH
+
+
D1
C7 47 uF
C6 560 uF
PS2501-2
R8
R10 2 MΩ D9
100 Ω
R11 500 kΩ
LED2 R5 .15 Ω 50W
R6 .15 Ω 50W
R7 .15 Ω
R9 Z1 15V
R24
SHORT
Z3 600V
ELECTRODE WORKPIECE
SENSE
DANGER
+
Q3
R28 2.2 MΩ
R4 60 kΩ
C5 560 uF
LEDs have typ. 1.17Vf
CASE
Q2
C4 560 uF
IRG4PSC71KD 60A ultrafast
100 uH CASE
+
25A
VS
DISCHARGE CAPV
+ BR2
165 Vp-p 0 Voffset 60 Hz
C15 100 nF
U7
IRG4PC30KD 16A ultrafast
2200 uF
+
C2 33 uF
Q1
Thermistor
R3 0.5 Ω
DISCHARGE
1.5A
50 kΩ C3 200V
T
R25
1.0 kΩ
+15V
OUT GND U1
CHARGE DANGER
XXX HO
1
DISCHARGE_EN
COM
LED1
+15V
+15V
C14
PS2501-4 ISO_5V_D
7815
(<400nF)
BOOST
LO
U5
U4-4
18V secondary
C13 100 nF
XXX R22
+
6.8 MΩ
+
CHARGE
VS
U4-3
Electrode current liimiting
(optional)
BR1
R21
1.0 kΩ
1.0 kΩ
(optional)
U3-1 R27
R1
XXX HO
1/4 LM324
R19 50 kΩ
115V primary
VB
COM
BOOST_EN
6.8 MΩ
+15V
LIN
ISO_5V_C PS2501-4
U3-4 R26
SENSE
100 kΩ
1
1%
U4-1
IR2117
CAPV
Explicit Charge Disable
+
1 MΩ 1% R13
Z2 15V R23
Note: ~3mA discharge of C7 through R23 (Time constant of ~5s)
R20 1 kΩ
VSET_PWM
1% +15V
R12
SENSE
+15V
PS2501-4 ISO_5V_A
30.1 kΩ
C12 100 nF
U6
IR2108
+15V
+ V+
RA1: 820 Ω CTS 770-101-821 R14
D7
RESET
GND
Computes Gnd-referenced Vcap
D6
+
6
ICM7555
1 ISO_5V VSET_PWM 2 3 CHARGE_EN 4 DISCHARGE_EN BOOST_EN 5
U2-1 PS2501-2
SPARK
1.1V
50W
100 Ω LED3
SPARK OK
‘GARDEN OF EDM’ POWER SUPPLY ~50A, ~300VDC. Designed by C. Scott Ananian (
[email protected])
2.2V
D2
100 Ω
U2-2
CASE
D8
ISO_GND
BOOST
0.0V
Q4