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FS-1010
(3) Power supply board
The power supply board provides the AC power input and DC power and outputs. The high voltage
bias generator circuit is mounted on a separate board. A simplified schematic diagram is shown
below.
Figure 4-3-8 Power supply board circuit block diagram
FET
(Q1)
Switching/
Over
current
detection
circuit
Power
switch
Current
fuse
Noise
filter
circuit
Transformer
(T1)
24 V DC
rectifier/
smooth-
ing circuit
24 V DC
shutoff
circuit
Over voltage
detection
circuit
Photo-
coupler
(PC1)
Photo-
Tr iac
(PC2)
Tr iac
(TRC1)
Heater
lamp
AC
input
5 V DC
rectifier/
smooth-
ing circuit
Thermistor
Cooling fan
+24 V COM
+24 V COM
THERM
+24 V
HEAT
EXITN
PGND, SGND
+5 V
FAN
SLEEP
Thermal
cutout
Transistor
(Q8)
ZCROSS
Photo-
coupler
(PC3)
(SW1) (F1)
Exit
sensor
Zero cross signal
detection circuit
Power supply unit