Sharp R-951M Service Manual ▷ View online
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.
R-951M - 10
DESCRIPTION OF LSI
LSI(IZA880DR)
The I/O signal of the LSI(IZA880DR) are detailed in the following table.
Pin No.
Signal
I/O
Description
1
C1
IN
Terminal not used.
2
VL1
IN
Power source voltage input terminal.
Standard voltage for LCD.
3-6
AN7-AN4
IN
Heating constant compensation terminal.
7
AN3
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.
thermistor, this input is converted into temperature by the A/D converter built
into the LSI.
8
AN2
IN
Input signal which communicates the door open/close information to
LSI.
LSI.
Door closed; "H" level signal.
Door opened; "L" level signal.
Door opened; "L" level signal.
9-10
AN1-AN0
IN
Terminal not used.
11
P57
IN
Input signal which communicates the door open/close information to
LSI.
LSI.
Damper opened; "H" level signal (0V:GND).
Damper closed; "L" level signal (-5V:VC).
Damper closed; "L" level signal (-5V:VC).
12
P56
OUT
Signal to sound buzzer.
A: key touch sound.
B: Completion sound.
C: When the temperature of the oven
B: Completion sound.
C: When the temperature of the oven
cavity reaches the preset
temperature in the preheating
mode, or when the preheating hold
time (30 minutes) is elapsed.
temperature in the preheating
mode, or when the preheating hold
time (30 minutes) is elapsed.
13
P55
Terminal not used.
14-18
P54-P50
OUT
Terminal not used.
19
P47
OUT
Oven lamp and turntable motor driving signal(Square Waveform : 50Hz).
To turn on and off shut-off relay (RY1).
The square waveform voltage is
delivered to the relay (RY1) driving
circuit and relays (RY2,RY3,RY4)
control circuit.
The square waveform voltage is
delivered to the relay (RY1) driving
circuit and relays (RY2,RY3,RY4)
control circuit.
20
P46
IN/OUT
Terminal not used.
21
P45
OUT
Back light driving signal.
To change the brightness of the back light (Light emitting diodes LD1 - LD5).
The square waveform voltage is delivered to the back light driving circuit.
The square waveform voltage is delivered to the back light driving circuit.
22
P44
OUT
Timing signal output terminal for temperature measurement (oven).
"H" level (GND) : Thermistor OPEN timing.
"L" level (-5V) : Temperature measuring timing.
"L" level (-5V) : Temperature measuring timing.
23
INT1
IN
Terminal not used.
24
INT0
IN
Signal to synchronized LSI with commercial power source
frequency(50Hz).
frequency(50Hz).
This is basic timing for time processing of LSI.
25
P41
IN
Terminal not used.
26
P40
OUT
Signal similar to P44.
Timing signal output terminal for temperature measurement.
27
P77
OUT
Convection heating element driving signal.
To turn on and off the heating element
relay (RY3). "L" level during convection
cooking or dual cooking, "H" level
otherwise.
relay (RY3). "L" level during convection
cooking or dual cooking, "H" level
otherwise.
A
B
C
H: GND
L
0.12 sec
2.4 sec
1.2 sec
1.2 sec
20 msec
During cooking
H
L
20 msec
H : GND
L (-5V)
ON
OFF
During
cooking
L
GND
H.
(Convection or dual)
TOUCH CONTROL
CONT
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R-951M - 11
ON
OFF
During
cooking
L
GND
H.
(Grill or dual)
Pin No.
Signal
I/O
Description
ON/OFF time ratio in Micro
cooking
(a. 32second time base)
cooking
(a. 32second time base)
ON/OFF time ratio in Micro
cooking
(a. 48second time base)
cooking
(a. 48second time base)
MICRO
ON
OFF
COOK
100%
100%
32sec.
0sec.
70%
24sec.
8sec.
50%
18sec.
14sec.
30%
12sec.
20sec.
10%
6sec.
26sec.
MICRO
ON
OFF
COOK
100%
100%
48sec.
0sec.
70%
36sec.
12sec.
50%
26sec.
22sec.
30%
16sec.
32sec.
10%
8sec.
40sec.
29
P75
OUT
Magnetron high-voltage circuit driving signal.
To turn on and off the cook
relay (RY2). In 100%
POWER operation, the
signals hold "L" level during
microwave cooking and "H"
level while not cooking. In
other cooking modes (70%,
50%, 30%, 10%) the signal
turns to "H" level and "L" level
in repetition according to the
power level.
relay (RY2). In 100%
POWER operation, the
signals hold "L" level during
microwave cooking and "H"
level while not cooking. In
other cooking modes (70%,
50%, 30%, 10%) the signal
turns to "H" level and "L" level
in repetition according to the
power level.
30
P74
OUT
Terminal not used.
31
P73
OUT
Damper motor relay driving signal.
To turn on and off shut-off relay (RY7).
32
P72
OUT
Fan motor driving signal.
To turn on and off the fan motor
relay RY5. "L" level during cooking,
or for 5 minutes after grill cooking or
dual cooking. "H" level otherwise.
relay RY5. "L" level during cooking,
or for 5 minutes after grill cooking or
dual cooking. "H" level otherwise.
33
P71
IN
Convection motor driving signal.
To turn on and off shut-off relay
(RY6). "L" level during
CONVECTION; "H" level otherwise.
(RY6). "L" level during
CONVECTION; "H" level otherwise.
34
P70
IN
Connected to VC.
35
RESET
IN
Auto clear terminal.
Signal is input to reset the LSI to the initial state when power is applied.
Temporarily set to "L" level the moment power is applied, at this time the LSI
is reset. Thereafter set at "H" level.
Temporarily set to "L" level the moment power is applied, at this time the LSI
is reset. Thereafter set at "H" level.
36
XCIN
IN
Terminal not used.
37
XCOUT
OUT
Terminal not used.
38
XIN
IN
Internal clock oscillation frequency input setting.
The internal clock frequency is set by inserting the ceramic filter oscillation
circuit with respect to XIN terminal.
circuit with respect to XIN terminal.
39
XOUT
OUT
Internal clock oscillation frequency control output.
Output to control oscillation input of XOUT.
40
VSS
IN
Power source voltage: -5V.
VC voltage of power source circuit input.
41-44
P27-P24
IN/OUT
Terminal not used.
45
P23
IN
Signal coming from touch key.
When any one of G2 line keys on key matrix is touched, a corresponding
signal from P11, P12, P13, P14, P15, P16 and P17 will be input into P23.
When no key is touched, the signal is held at "L" level.
signal from P11, P12, P13, P14, P15, P16 and P17 will be input into P23.
When no key is touched, the signal is held at "L" level.
46
P22
IN
Signal similar to P23.
When any one of G5 and G9 line keys on key matrix is touched, a
corresponding signal will be input into P22.
corresponding signal will be input into P22.
47
P21
IN
Signal similar to P23.
When any one of G7 line keys on key matrix is touched, a corresponding
signal will be input into P21.
signal will be input into P21.
48
P20
IN
Signal similar to P23.
When any one of G11 line keys on key matrix is touched, a corresponding
signal will be input into P20.
signal will be input into P20.
ON
OFF
L
GND
H.
ON
OFF
During cooking, or for 5 minutes or more
after grill cooking, convection cooking or
dual cooking
after grill cooking, convection cooking or
dual cooking
L
GND
H.
ON
OFF
During
cooking
L
GND
H.
(Convection or dual)
28
P76
OUT
Grill heating element driving signal.
To turn on and off the bottom element
relay (RY4). "L" level during grill
cooking or dual cooking, "H" level
otherwise.
relay (RY4). "L" level during grill
cooking or dual cooking, "H" level
otherwise.
TOUCH CONTROL
CONT
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R-951M - 12
52
P14
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P20 - P23
terminal while one of G6 line keys on matrix is touched.
terminal while one of G6 line keys on matrix is touched.
53
P13
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P20 - P23
terminal while one of G4 line keys on matrix is touched.
terminal while one of G4 line keys on matrix is touched.
54
P12
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P20 - P23
terminal while one of G3 line keys on matrix is touched.
terminal while one of G3 line keys on matrix is touched.
55
P11
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P20 - P23
terminal while one of G1 line keys on matrix is touched.
terminal while one of G1 line keys on matrix is touched.
56
P10
OUT
Terminal not used.
57-60
SEG33-SEG30
Terminal not used.
61-90
SEG29-SEG0
OUT
Segment data signal.
Connected to LCD.
The relation between signals are as follows:
The relation between signals are as follows:
LSI signal (Pin No.)
LCD (Pin No.)
LSI signal (Pin No.) LCD (Pin No.)
SEG 0 (90) ................................ 1
SEG15 (75) ........................... 29
SEG 1 (89) ................................ 2
SEG16 (74) ........................... 28
SEG 2 (88) ................................ 3
SEG17 (73) ........................... 27
SEG 3 (87) ................................ 4
SEG18 (72) ........................... 26
SEG 4 (86) ................................ 5
SEG19 (71) ........................... 25
SEG 5 (85) ................................ 6
SEG20 (70) ........................... 24
SEG 6 (84) ................................ 7
SEG21 (69) ........................... 11
SEG 7 (83) ................................ 8
SEG22 (68) ........................... 23
SEG 8 (82) ................................ 9
SEG23 (67) ........................... 22
SEG 9 (81) .............................. 10
SEG24 (66) ........................... 12
SEG10 (80) ............................. 34
SEG25 (65) ........................... 13
SEG11 (79) ............................. 33
SEG26 (64) ........................... 14
SEG12 (78) ............................. 32
SEG27 (63) ........................... 15
SEG13 (77) ............................. 31
SEG28 (62) ........................... 16
SEG14 (76) ............................. 30
SEG29 (61) ........................... 17
91
VCC
IN
Connected to GND.
92
VREF
IN
Connected to GND.
93
AVSS
IN
Connected to VC.
94
COM3
OUT
Common data signal: COM3.
Connected to LCD (Pin No. 21).
95
COM2
OUT
Common data signal: COM2.
Connected to LCD (Pin No. 20).
96
COM1
OUT
Common data signal: COM1.
Connected to LCD (Pin No. 19).
97
COM0
OUT
Common data signal: COM0.
Connected to LCD (Pin No. 18).
98-99
VL3-VL2
IN
Power source voltage input terminal.
Standard voltage for LCD.
100
C2
IN
Terminal not used.
Pin No.
Signal
I/O
Description
TOUCH CONTROL
CONT
...
49
P17
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P20 - P23
terminal while one of G12 line keys on matrix is touched.
terminal while one of G12 line keys on matrix is touched.
50
P16
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P20 - P23
terminal while one of G10 line keys on matrix is touched.
terminal while one of G10 line keys on matrix is touched.
51
P15
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P20 - P23
terminal while one of G8 line keys on matrix is touched.
terminal while one of G8 line keys on matrix is touched.
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