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17
R-4G75(W)M
R-4G75(B)M
R-4G75(B)M
The touch control section consists of the following units
as shown in the touch control panel circuit.
as shown in the touch control panel circuit.
(1) Key Unit
(2) Control Unit
(2) Control Unit
The principal functions of these units and the signals
communicated among them are explained below.
communicated 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 through P05,P06,P07,
P10,P12 and P14. When a key pad is touched, a signal is
completed through the key unit and passed back to the
LSI through P24,P25,P26 and P27 to perform the function
that was requested.
The key unit is composed of a matrix, signals generated in
the LSI are sent to the key unit through P05,P06,P07,
P10,P12 and P14. When a key pad is touched, a signal is
completed through the key unit and passed back to the
LSI through P24,P25,P26 and P27 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 and indica-
tor circuit.
Control unit consists of LSI, power source circuit, synchro-
nizing signal circuit, ACL circuit, buzzer circuit and indica-
tor 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 voltages necessary in the control
unit.
unit.
Symbol
Voltage
Application
VC
-5V
LSI(IC1)
VP
-26V
Fluorescent display tube : Grid
and anode voltage
and anode voltage
VF1
3Vac
Filament of fluorescent display
tube
tube
VF2
(VF1 to VF2 voltage)
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 Circuit
A circuit to generate a signal 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
noticing sounds (key touch sound and completion sound).
noticing 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, fan motor, turntable motor, grill
heater and light the oven lamp.
heater and light the oven lamp.
8) Indicator Circuit
Indicator element is a Fluorescent Display.
Basically, a Fluorescent Display is triode having a cath-
ode, a grid and an anode. Usually, the cathode of a
Fluorescent Display is directly heated and the filament
serves as cathode.
The Fluorescent Display has 6-digits, 13-segments are
used for displaying figures.
Basically, a Fluorescent Display is triode having a cath-
ode, a grid and an anode. Usually, the cathode of a
Fluorescent Display is directly heated and the filament
serves as cathode.
The Fluorescent Display has 6-digits, 13-segments are
used for displaying figures.
9) Absolute Humidity Sensor Circuit
The circuit detects absolute humidity of a food whith is
under cooking, to allow its automatic cooking.
under cooking, to allow its automatic cooking.
TOUCH CONTROL PANEL
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