Canon LBP-1210 Service Manual page 97

4. High-Voltage Power Supply Circuit
a. Outline
IC201
CPU
PRDCC
/DCPWM
30
PRACC
/PRAC
31
CRGSNS
P31/AD1
43
DVACC
DEVAC
32
TRPWM
TRFP
37
TRNFOT
TRFM
36
IC202
TRCRNT
P32/AD2
44
This circuit is structured with the primary charging bias circuit, developing bias circuit, and
transfer charging bias circuit.
The primary charging bias circuit generates negative AC and DC voltage to apply the com-
bined voltage of these AC and DC to the primary charging roller. It also applies the negative DC
voltage to the fixing film unit through the pressure roller. Also, this circuit detects cartridge
presence.
The developing bias circuit generates negative AC and DC voltage to apply the combined volt-
age to the developing cylinder.
Engine controller PCB
High-voltage power supply circuit
Primary charging bias circuit
IC301
DC voltage
generation
circuit
Combined
IC202 IC301
AC voltage
generation
circuit
Developing bias circuit
DC voltage
generation
circuit
Combined
IC301
AC voltage
generation
circuit
Transfer charging bias circuit
Positive voltage
generation circuit
Negative voltage
generation circuit
Figure 2-2-4
CHAPTER 2
Developing cylinder
FB J305
Primary
charging
roller
PR1 J304
Fixing
film unit
J303
Transfer
charging
roller
DEV J301
Pressure roller
TRS J302
Photos
ensitive
drum
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