Sharp R-2397 User Manual
Page 20
R-2397
18
DESCRIPTION OF LSI
LSI(IZA646DR)
The I/O signal of the LSI(IZA646DR) is detailed in the following table.
Pin No.
Signal
I/O
Description
1
VREF
IN
Reference voltage input terminal.
A reference voltage applied to the A/D converter in the LSI. Connected to GND.(0V)
2
IN7
IN
Temperature measurement input: MAGNETRON 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.
3
IN6
IN
Temperature measurement input: EXHAUST 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.
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
Temperature measurement input: INTAKE 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.
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 ocurrence.)
16
P41
OUT
Terminal not used.
17
P40
OUT
Oven lamp, Blower motor and Stirrer motor 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: Guydance sound.
C: Completion sound.
24
P31
IN
Signal synchronized with commercial power source frequency.
This is basic timing for all time processing of LSI.
25
P30
OUT
Terminal not used.
26
CNVSS
IN
Connected to Vc.(-5V)
GND
-5V
48 sec.
OFF
ON
H
L
20 msec
During cooking
A
B
C
0.12 sec
2.4 sec
1.2 sec
1.2 sec
GND
-5V
T
200
µ
sec.
200
µ
sec.
H : GND
L (-5V)
20 msec