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OPERATIONS AND TIMING
COPYRIGHT
©
1998 CANON INC. CANON NP6621 REV.0 FEB. 1998 PRINTED IN JAPAN (IMPRIME AU JAPON)
G. Controlling the DevelopingBias
1. Outline
Figure 3-308 shows the circuit that controls the
developing bias, and the circuit has the following
functions:
• Turns ON/OFF the developing bias AC
component.
• Turns ON/OFF the developing bias DC
component.
Controls the voltage level of the developing
bias DC component.
Controls the developing bias DC component
to a constant voltage.
Figure 3-308
Composite power supply PCB
Developing
DC bias drive
circuit
T4
24V
Developing
DC bias voltage
detection circuit
Developing AC bias transformer
T301
BPWM
BIASS
J5
J307
Developing AC
transformer
drive circuit
Microprocessor
Photosensitive
drum
Developing
cylinder
AE sensor
Copy Density key DC controller PCB
Q301
Microprocessor Copy density
correction volume
VR850
ACBIAS