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R-8000GK
16
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.
in the touch control panel circuit.
(1) Tact switch circuit on the CPU unit and the control unit (switch unit).
(2) Control Unit (The control unit consists of Power unit and CPU unit.)
The principal functions of these units and the signals communi-
cated among them are explained below.
cated among them are explained below.
Tact Switch Circuit
The tact switch circuit is composed of a matrix, signals AN0-AN7
generated in the LSI are sent to the tact switches. When a tact
switch is touched, a signal is completed through the tact switch
circuit and passed back to the LSI through PB0-PB3 to perform
the function that was requested.
The tact switch circuit is composed of a matrix, signals AN0-AN7
generated in the LSI are sent to the tact switches. When a tact
switch is touched, a signal is completed through the tact switch
circuit and passed back to the LSI through PB0-PB3 to perform
the function that was requested.
Control Unit
Control unit consists of LSI, power source circuit, synchronizing
signal circuit, reset circuit, buzzer circuit, temperature measure-
ment circuit, relay watching circuit, input voltage watching circuit
and indicator circuit.
Control unit consists of LSI, power source circuit, synchronizing
signal circuit, reset circuit, buzzer circuit, temperature measure-
ment circuit, relay watching circuit, input voltage watching circuit
and indicator circuit.
1) LSI (IC-1)
This LSI controls the temperature measurement signal, tact
switch strobe signal, relay driving signal and indicator signal.
And also LSI watches the relay operation and the primary
input voltage.
switch strobe signal, relay driving signal and indicator signal.
And also LSI watches the relay operation and the primary
input voltage.
2) Power Source Circuit
This circuit generates the voltage necessary for the control
unit from the AC line voltage.
unit from the AC line 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 incorporates
a very small error because it works on commercial frequency.
compose a basic standard time in the clock circuit. It incorporates
a very small error because it works on commercial frequency.
4) Reset Circuit
A circuit to generate a signals which resetting the LSI to the
initial state when power is applied.
initial state when power is applied.
5) Buzzer Circuit
The buzzer is responds to signals from the LSI to emit
noticing sounds (tact switch touch sound and completion
sound).
noticing sounds (tact switch touch sound and completion
sound).
6) Temperature Measurement Circuit : (OVEN THERMISTOR)
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 applied to LSI. The LSI uses this information to control
the relay and display units.
The variation of resistance according to sensed temperature
is detected by the temperature measurement circuit and the
result applied to LSI. The LSI uses this information to control
the relay and display units.
7) Relay Operation Watching Circuit
This circuit watches so that the three (3) relays for the top
heating element, the side heating element and the power
transformer do not operate at the same time. This circuit
consists of the transistor Q24 - Q27 and resistors R23 - R26.
heating element, the side heating element and the power
transformer do not operate at the same time. This circuit
consists of the transistor Q24 - Q27 and resistors R23 - R26.
8) Input Voltage Watching Circuit
This circuit watches the primary input voltage.
9) Door Sensing Switch
A switch to inform the LSI if the door is open or closed.
10) Relay Circuit
To drive the magnetron, heating elements, fan motor, jet
motor, turntable motor and light the oven lamp.
motor, turntable motor and light the oven lamp.
11) Indicator Circuit
Indicator element is a Fluorescent Display.
Basically, a Fluorescent Display is triode having a cathode,
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 10-digits, 42-segments are
used for displaying figures.
Basically, a Fluorescent Display is triode having a cathode,
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 10-digits, 42-segments are
used for displaying figures.
12) Memory Processor (IC-2)
This is a memory IC, responsible for memory function.
DESCRIPTION OF LSI (IC-1)
LSI(IC-1):
The I/O signals of the LSI(IC-1) are detailed in the following table.
The I/O signals of the LSI(IC-1) are detailed in the following table.
Pin No.
Signal
I/O
Description
1
AN5
OUT
Tact switch strobe signal.
Signal applied to tact switch section (SW1, SW4, SW7, SW10).
Signal applied to tact switch section (SW1, SW4, SW7, SW10).
2
AN4
OUT
Turminal not used.
3
AN3
OUT
Tact switch strobe signal.
Signal applied to tact switch section (SW14, SW18, SW22).
Signal applied to tact switch section (SW14, SW18, SW22).
4
AN2
OUT
Tact switch strobe signal
Signal applied to tact switch section (SW13, SW17, SW21).
Signal applied to tact switch section (SW13, SW17, SW21).
5
AN1
OUT
Tact switch strobe signal.
Signal applied to tact switch section (SW12, SW16, SW20).
Signal applied to tact switch section (SW12, SW16, SW20).
6
AN0
OUT
Tact switch strobe signal.
Signal applied to tact switch section (SW11, SW15, SW19, SW23).
Signal applied to tact switch section (SW11, SW15, SW19, SW23).
7
AN15
IN
Primary input voltage watching terminal.
The LSI is watching the primary input voltage through this terminal.
The LSI is watching the primary input voltage through this terminal.
8-10
AN14-AN12
IN
Input terminal to change the specification according to the model.
11
AN11
IN
Temperature measurement input: OVEN THERMISTOR.
By inputting DC voltage corresponding to the temperature detected by the thermistor, this
input is converted into temperature by the A/D converter built into the LSI.
By inputting DC voltage corresponding to the temperature detected by the thermistor, this
input is converted into temperature by the A/D converter built into the LSI.
12
AN10
IN
Input signal which communicates the door open/close information to LSI.
Door closed; “H” level
Door closed; “H” level
µµ(0V).
Door opened; “L” level signal(-5V).
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