LG LSC27990TT Service Manual page 30

EXPLANATION FOR MICOM CIRCUIT
1-11. Fan motor driving circuit (freezer, mechanical area)
1. The circuit cuts all power to the fan drive IC, resulting in a standby mode.
2. This circuit changes the speed of the fan motor by varying the DC voltage between 7.5 Vdc and 16 Vdc.
3. This circuit stops the fan motor by cutting off power to the fan when it senses a lock-up condition.
®, ® part @ part ® part
Motor OFF 5V 2V or less 2V or less
Motor ON 2 -3V 12 - 14V 8- 16V
(1) G R-G277STSA(LSC27990TT)
P54
C-FAN PWM
53
PSI 50
C-FAN LOCK
ICI
(MIOOM)
P53 52
F-FAN PWM
P50 49
F-FAN LOCK
R38
4,7K
33O
- DI4
FRI07 L3
CEIO
TDI5
_ CCl7'
220uF 7
R40,' _ FRI07 223
/ZSV T
IOK
330
R45
R45
3,9K
R47'
IOK
CCI8.
DI7 CEll
FRI07 220uF -CCI9'
/25V T 223
RSO _-F_51*
2",<VV_ 4 4"7K
0C20_
I02
13
12
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