Kyocera FS-1030D - Power Supply Unit

2G6
2-3-8
2-3-3 Power supply unit
The Power supply unit 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 2-3-6 Power supply unit circuit block diagram
FET
(Q1)
Switching/
Over
current
detection
circuit
Power
switch
Current
fuse
Current
fuse
Noise
filter
circuit
(L1)
Transformer
(T1)
24 V DC
rectifier/
smooth-
ing circuit
24 V DC
shutoff
circuit
Over voltage
detection
circuit
Photo-
coupler
(PC1)
Photo-
coupler
(PC5)
Photo-
Triac
(PC2)
Triac
(TRA1)
Heater
lamp
AC
input
5 V DC
rectifier/
smooth-
ing circuit
Fuser
thermistor
Cooling fan
+24V1
+24V2
+24V1
THERM
HEATN
EXITN
PGND, SGND
+5 V
FAN
SLEEP
Thermal
cutout
Transistor
(Q121)
ZCROSS
Photo-
coupler
(PC4)
(SW1) (F1)
(F2)
Exit
sensor
(PC3)
Zero cross signal
detection circuit
Power supply unit
C5
D1
+