Canon PC920 Service Manual page 44

CHAPTER 2 BASIC OPERATION
2. Inputs to the DC Controller (2/2)
+24V
AE sensor PCB
Control panel
PCB
SW309
2-8
+24V
J601
J107-4
-3
-2
-1
J301 J111
J111-15
J111-16
J62
J102-2
-3
-4
-5
Figure 2-106
COPYRIGHT © 1999 CANON INC.
AE
When the light reflected by the original increases,
AEREF the voltage increases.
The keys and the LEDs are wired in a matrix
in the control panel PCB, and the DC controller
turns on or flashes the LEDs and reads key inputs.
PWOFF
DIG1
The variation in the resistance of the fixing heater
HEAT0
is corrected in three levels based on combinations
DIG1
of 2-bit signals.
HEAT1
CANON PC800s/900s REV.0 AUG. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
DC controller PCB