Fairchild AN-7511 User Manual
Page 10
©2002 Fairchild Semiconductor Corporation
Application Note 7511 Rev. A1
FIGURE 15A. THIS ALL-ENCOMPASSING PROTECTION SYSTEM PROVIDES THREE INDEPENDENT SHUTDOWN FUNCTONS -
ONE EACH FOR THE UPPER AND LOWER IGTS AND THE HIGH-VOLTAGE SUPPLY.
FIGURE 15B. THIS CIRCUIT PROVIDES CHOPPER DRIVE FOR THE COPPER-WIRE
SENSOR IN FIGURE 15A.
FIGURE 15C. SHOWS THE HIGH-VOLT-
AGE SHUTDOWN CIRCUIT.
50 TO 320V DC
24V
3.9k
750k
3.3k
2.7k
2N5355
470pF
0.01
µ
F
10A
2k
5
µ
F
20V
150
2N5232
15V
5
µ
F
25V
220k
2.2k
0.001
µ
F
H11F3
H11F3 TO
CONTROL CIRCUIT
39
470
pF
390
20A
2k
2m
Ω
(1” #24 AWG COPPER)
POWER
SUPPLY
CURRENT
SENSE AND
CHOPPER
AC
AMPLIFIER
LATCHING
FAST
COMPARATOR
10ms
RESET
IGT POWER SWITCHES
A139M
50
µ
H
10k
180k
47k
39k
0.001
µ
F
1k
2N5306
C203B
0.02
µ
F
22k
H11AV2 TO PZO SHUTDOWN
H11AV2 TO HI-V SHUTDOWN
22
0.2
µ
F
2
1
TO
DRIVE
DT230F
TO
MOTOR
TIMER
555
1 3
CHOPPER DRIVE
TO PIEZO
DRIVERS
5V
150
150
180
0.002
µ
F
5.1k
2N5232
H11F3
H11F3
100
180
0.002
µ
F
5.1k
2N5232
0.005
µ
F
150
DT230F
(3)
47k
H11AV2
10
µ
F
10V
ALL OPTOCOUPLERS GO TO PROTECTION CIRCUIT
SG3524
15
16
10
8
HIGH-VOLTAGE SHUTDOWN
24V
TO
CONTROL
5V
2.2k
0.005
µ
F
1M
Application Note 7511