Samsung RL44Q Series Service Manual page 188

REFERENCE INFORMATION 5. SELF DIAGNOSIS & TROUBLE SHOOTING
9-3-2-2) Power Supplier (AC TRANSFORMER Method)
1) On impression to power source "A", the voltage across
supplied from a stepped-down voltage on the secondary side of the transformer and this is
rectified to DC voltage through a rectification circuit, Diode D101~D104. And then, an output of
12V/DC made by REG1(7812) Regulator is supplied to the Relay, the Panel PCB, and the
Motor-operated Damper, and an output of 5VDC made by REG2(7805) is supplied to the
Refrigerator control MICOM and the Panel PCB. With these power, the whole PCB parts are
properly operated.
2) On impression to power source "B", the voltage across
supplied from a stepped-down voltage on the secondary side of the transformer and this is
rectified to DC voltage through a rectification circuit, Diode D105~D108. An output of around
13.2VDC is supplied to the Motor and the Damper.
※ The power of the power source "B" can vary according to the option specification.
9-3-2-3) Oscillation Circuit
1) This is the oscillation circuit to generate time synchronizing clock and to calculate time for the
sending and receiving of information of the components in the MICOM.
Power Source
Power "A"
12VDC
5VDC
Power "B"
13.2DVC
- of the CN10 is around 16V/AC
① ③
- of the CN10 is around 14V/AC
⑤ ⑦
Terminal
Xin (#19)
Xout (#18)
188
Circuit
Peripheral Circuit of
refrigerator control, MICOM
"A"
Relay, Sensor part, Display
part
Motor-operated Damper
control (Refrigerator and
Chammart compartments)
"B" Power source for BLDC
Motor (Freezer Fan)
Oscillating Frequency
8.0MHz
8.0MHz