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871M - 8
TOUCH CONTROL / DESCRIPTION OF LSI
TOUCH CONTROL PANEL ASSEMBLY
OUTLINE OF TOUCH CONTROL PANEL
The touch control section consists of the following units as
shown in the touch control panel circuit.
shown in the touch control panel circuit.
(1) Key Unit
(2) Control Unit
(2) Control Unit
The principal functions of these units and signals communi-
cated among them are explained below.
cated 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.
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, synchroniz-
ing signal circuit, ACL circuit, buzzer circuit, temperature
measurement circuit, indicator circuit, encoder circuit, and
back light circuit.
ing signal circuit, ACL circuit, buzzer circuit, temperature
measurement circuit, indicator circuit, encoder circuit, and
back light circuit.
1) LSI
This LSI controls the key strobe signal, relay driving signal
for oven function and indicator 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.
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, fan motor,
turntable motor and light the oven lamp.
turntable motor and light the oven lamp.
8) Back Light Circuit
A circuit to drive the back light (Light emitting diodes LD1
- LD5).
- 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.
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