Canon LBP-1210 Service Manual page 93

3. Fixing Control Circuit
a. Outline
Engine controller PCB
FU101
AC input
FSRD
FSRD
39
FSRTH
P30/AD0
42
IC201
CPU
RLYD
P52/PT03
38
FSRSTH
P33/AD3
45
This printer employs the on-demand fixing method. The fixing unit contains a fixing film unit
that is embedded with a fixing heater, thermistors, and thermal fuse, and a pressure roller.
The fixing heater is a plate-shaped heater that heats up the fixing film.
The thermistors are installed in the center and at the end of the fixing heater (H701). These
thermistors detect the fixing heater temperature. The main thermistor (TH701), in the center,
controls the fixing temperature, while the sub thermistor (TH702), at the end, detects the abnor-
mal high-temperature of the fixing heater end.
Sub thermistor
(TH702)
Fixing heater
drive circuit
Q101
SSR101
+3.3V
+3.3V
Fixing control circuit
Figure 2-2-3
Fixing film unit
Fixing heater
Pressure
(H701)
roller
+3.3V
RL101
Fixing heater
safety circuit
+24U
IC301
2
1
Q103
3
+24V +24V
IC202
6
7
Q104
5
CHAPTER 2
Thermal fuse
(FU1132)
Main thermistor
(TH701)
+3.3V
R214
+3.3V
R215
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