Sharp MODEL R-2197, Service Manual

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R-2197
15
7-8 AN5-AN4 IN Terminal to change functions according to the model.
Signal in accordance with the model in operation is applied to set up its function.
9-10 AN3-AN2 IN Terminal not used.
11 AN1 IN Input signal which communicates the door open/close information to LSI.
Door closed; "L" level signal (0V).
Door opened; "H" level signal (+5V).
12 AN0 IN Terminal not used.
13 P55 OUT Magnetron high-voltage circuit driving signal.
To turn on and off the cook relay. In 100% power level operation, "H" level during
cooking; "L" 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% 32sec. 0sec. 40% 16sec. 16sec.
90% 30sec. 2sec. 30% 12sec. 20sec.
80% 26sec. 6sec. 20% 8sec. 24sec.
70% 24sec. 8sec. 10% 6sec. 26sec.
60% 22sec. 10sec. 0% 0sec. 32sec.
50% 18sec. 14sec.
14-15 P54-P53 OUT Terminal not used.
16-18 P52-P50 IN Terminal not used.
19 P47 OUT Signal to sound buzzer.
This signal is to control the 2.5kHz con-
tinuous signal through IC3.
A: key touch sound.
B: Guidance sound.
C: Completion sound.
20 P46 OUT Oven lamp, Fan motor and Antenna motor driving signal. (Square Waveform :
50Hz)
To turn on and off the shut-off relay (RY3). The
Square waveform voltage is delivered to the
RY3 driving circuit and relays(RY2, COOK RE-
LAY) control circuit.
21 P45 OUT Digit selection signal.
The relation between digit signal and digit are
as follows:
Digit signal Digit
P42 ..................... 1st.
P43 .................... 2nd.
P44 ..................... 3rd.
P45 ..................... 4th.
Normally, one pulse is output in every ß
period, and input to the grid of the light-
emitting diode.
22-24 P44-P42 OUT Digit selection signal.
Signal similar to P45.
25 INT1 IN Signal synchronized with commercial power source frequency.
This is basic timing for all time processing of LSI.
26 P40 IN Connected to GND through resistor.
Pin No. Signal I/O Description
+5V
GND
32 sec.
ON
OFF
A
0.12 sec
2.4 sec
1.2 sec
+5V
GND
T
200
µ
sec. 200
µ
sec.
1.2 sec
B
+5V
GND
C
+5V
GND
H
L
20 msec
During cooking
H
L
+5V
ß(50Hz)
P42
P43
P44
P45
GND
H : +5V
L : GND
20 msec