Sharp R-209FW, Руководство по обслуживанию

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R-209(IN)
R-209(W)
R-209(Y)
15
The control unit consists of the following circuits as shown in the control unit circuit.
The principal functions of these circuits and their related signals are explained below.
Control Unit
Control unit consists of LSI, reset circuit, power source circuit, relay circuit and synchronizing signal circuit.
1) Reset Circuit
This circuit generates a signal which resets the LSI to the initial state when power is supplied.
2) Potentiometer Circuit
The circuit makes setting of the power level by variable resistance.
3) Power Source Circuit
This circuit generates voltage necessary in the control unit from the AC line voltage. In addition, the synchronizing
signal is available in order to compose a basic standard time in the clock circuit.
Symbol Voltage Application
VDD +5V LSI(IC-1)
VSS 0V LSI(IC-1)
4) Relay Circuit
To drive the magnetron, fan motor, turntable motor and light the oven lamp.
5) Synchronizing Signal Circuit
The power source synchronizing signal is available in order to compose a basic standard time in the clock circuit.
It accompanies a very small error because it works on commercial frequency.
CONTROL UNIT ASSEMBLY
OUTLINE OF CONTROL UNIT