Sharp R-22AT Service Manual

19
R-22AT
R-23AM
R-24AT
Pin No. Signal I/O Description
2 IN7 IN Temperature measurement input: MAGNETRON THERMISTOR AND OVEN
THERMISTOR (2).
By inputting DC voltage corresponding to the temperature detected by the thermis-
tor, this input is converted into temperature by the A/D converter built into the LSI.
3 IN6 IN Temperature measurement input: OVEN THERMISTOR (1).
By inputting DC voltage corresponding to the temperature detected by the thermis-
tor, this input is converted into temperature by the A/D converter built into the LSI.
4 IN5 IN A/D input for troubleshooting Magnetron 1.
5 IN4 IN Terminal to change functions according to the model.
Signal in accordance with the model in operation is applied to set up its function.
6 IN3 IN A/D input for troubleshooting Magnetron 2.
7 IN2 IN Connected to GND.(0V)
8 IN1 IN Terminal not used.
9 IN0 IN Connected to VC.
10 P47 OUT Terminal not used.
11 P46 OUT Memory (EEPROM) clock output.
12 P45 IN/OUT Memory (EEPROM) data input/output.
13-14 P44-P43 OUT Magnetron high-voltage circuit driving signal.
To turn on and off the cook relay. In 100% power level operation, "L" level during
cooking; "H" level otherwise. In other power level operation (90, 80, 70, 60, 50, 40,
30, 20, 10 or 0%), "H" and "L" level is repeated according to power level.
Power level ON OFF Power level ON OFF
100% 48sec. 0sec. 40% 22sec. 26sec.
90% 44sec. 4sec. 30% 16sec. 32sec.
80% 40sec. 8sec. 20% 12sec. 36sec.
70% 36sec. 12sec. 10% 8sec. 40sec.
60% 32sec. 16sec. 0% 0sec. 48sec.
50% 26sec. 22sec.
15 P42 OUT Power supply output at thermistor detecting circuit.
(Output -5V in cooking only, but apply high impedance to others to prevent thermistor
from electrolytic corrosion occurrence.)
16 P41 OUT Terminal not used.
17 P40 OUT Oven lamp, Blower motor and Stirrer motors driving signal. (Square Waveform
: 50Hz)
To turn on and off the shut-off relay (RY1).
The Square waveform voltage is delivered to
the RY1 relay driving circuit and relays(RY3,
RY4, COOK RELAY) control circuit.
18-22 P37-P33 OUT Terminal not used.
23 P32 OUT Signal to sound buzzer.
This signal is to control the 2.5kHz
continuous signal.
A: key touch sound.
B: Guidance sound.
C: Completion sound.
24 P31 IN Signal synchronized with commercial power source frequency.
This is basic timing for all time processing of LSI.
GND
-5V
48 sec.
OFF
ON
H
L
20 msec
During cooking
H : GND
L (-5V)
20 msec
A
B
C
0.12 sec
2.4 sec
1.2 sec
1.2 sec
GND
-5V
T
200µsec.
200µsec.

Sharp R-22AT Specifications