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R-951M - 9
TOUCH CONTROL
CONT
...
OUTLINE OF TOUCH CONTROL PANEL
The touch control section consists of the following units as shown in the touch control panel circuit.
(1) Key Unit
(2) Control Unit
(2) Control Unit
The principal functions of these units and signals commu-
nicated among them are explained below.
nicated among them are explained below.
Key Unit
The key unit is composed of a matrix, signals generated in
the LSI are sent to the key unit from P11 - P17.
When a key pad is touched, a signal is completed through
the key unit and passed back to the LSI through P20 - P23
to perform the function that was requested.
the LSI are sent to the key unit from P11 - P17.
When a key pad is touched, a signal is completed through
the key unit and passed back to the LSI through P20 - P23
to perform the function that was requested.
Control Unit
Control unit consists of LSI, power source circuit, synchro-
nizing signal circuit, ACL circuit, buzzer circuit, tempera-
ture measurement circuit, relay circuit, indicator circuit
and back light circuit.
nizing signal circuit, ACL circuit, buzzer circuit, tempera-
ture measurement circuit, relay circuit, indicator circuit
and back light circuit.
1) LSI
This LSI controls the key strobe signal, relay driving
signal for oven function and indicator signal.
signal for oven function and indicator signal.
2) Power Source Circuit
This circuit generates voltage necessary in the control
unit.
unit.
Symbol
Voltage
Application
VC
-5.2V
LSI(IC1)
3) 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.
order to compose a basic standard time in the clock
circuit. It accompanies a very small error because it
works on commercial frequency.
4) ACL
A circuit to generate a signals which resets the LSI to
the initial state when power is supplied.
the initial state when power is supplied.
5) Buzzer Circuit
The buzzer is responsive to signals from the LSI to emit
audible sounds (key touch sound and completion
sound).
audible sounds (key touch sound and completion
sound).
6) Door Sensing Switch (Stop Switch)
A switch to "tell" the LSI if the door is open or closed.
7) Relay Circuit
To drive the magnetron, heating element, convection
fan motor, fan motor, turntable motor and light the oven
lamp.
fan motor, fan motor, turntable motor and light the oven
lamp.
8) Back Light Circuit
A circuit to drive the back light (Light emitting diodes
LD1 - LD5).
LD1 - LD5).
9) Indicator Circuit
This circuit consists of 7-digits, 30-segments and 4-
common electrodes using a Liquid Crystal Display.
common electrodes using a Liquid Crystal Display.
10) Temperature Measurement Circuit
The temperature in the oven cavity is sensed by the
thermistor. The variation of resistance according to
sensed temperature is detected by the temperature
measurement circuit and the result applies to LSI. The
result of detecting is given to LSI controlling the relay
and display.
thermistor. The variation of resistance according to
sensed temperature is detected by the temperature
measurement circuit and the result applies to LSI. The
result of detecting is given to LSI controlling the relay
and display.
11) Damper Switch
A switch to tell the LSI if the damper is open or close.
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