Samsung RL23DATS, Service Manual

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11. CIRCUIT DETAILS
11-1 Power Supply Part
220V
7812 7812
C104
104 C101
1000uF
50V
C102
170u
F25V C103
100u
F16V
12V
L.V.T
The AC input voltage will be stepped down by the transformer and be converted into the DC voltage
by the rectifying circuit (D101-104). The 1000F/35V wave filter capacitor will be used to filter out the
residue AC voltage and the manostat 7812 is used to output the steady 12V DC voltage that will be
used as the control voltage of the relay and display. The 12V DC voltage will be regulated by the
manostat 7805 to output the steady 5V voltage, which will be used as the output voltage of the chip
peripheral circuit and various signals (sensor, switch) .
Power supply
Vcc (DC 5V)
Vcc (DC 12V)
Applied circuit
Control voltage of the display and relay
chip peripheral power and sensor, bimetallic thermostat, door switch voltate
11-2 Reset Circuit Part
The reset circuit part enables the system program to return the system that meets power
trouble or abrupt power-off to the initial state by the memory of the core chip. At the very
beginning of the power-on, the reset chip voltage is LV, and becomes HV after normal
operation.
51951A
C202
104 C203
104
Vcc
RESET
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