Service manual

15
R-1512
R-1511
10 AN0 IN Used for initial balancing of the bridge circuit (absolute humidity sensor). This input is
an analog input terminal from the AH sensor circuit, and connected to the A/D converter
built into the LSI.
11-13 P57-P55 OUT Used for initial balancing of the bridge circuit (absolute humidity sensor).
14 CNTR0 OUT Signal to sound buzzer (2.0 kHz).
A: key touch sound.
B: Completion sound.
15 P53 OUT Used for initial balancing of the bridge circuit (absolute humidity sensor).
16 P52 OUT Oven lamp, fan motor and turntable motor driving signal
To turn on and off shut off relay (RY1). The
square waveform voltage is delivered to the
RY1 driving circuit and RY2 control circuit.
17 P51 OUT Used for initial balancing of the bridge circuit (absolute humidity sensor).
18 P50 OUT Terminal not used.
19 P47 OUT Magnetron high-voltage circuit driving signal.
To turn on and off the cook relay (RY2). The
signals holds “L” level during microwave
cooking and “H” level while not cooking. In
other cooking modes (variable cooking) the
signal turns to “H” level and “L” level in
repetition according to the power level.
20 P46 IN Signal coming from touch key.
When either G12 line on key matrix is touched, a corresponding signal out of P20 - P27
will be input into P46. When no key is touched, the signal is held at “H” level.
21 P45 IN Signal similar to P46.
When either G11 line on key matrix is touched, a corresponding signal will be input into P45.
22 P44 IN Signal similar to P46.
When either G10 line on key matrix is touched, a corresponding signal will be input into P44.
23 P43 IN Signal similar to P46.
When either G9 line on key matrix is touched, a corresponding signal will be input into P43.
24 INT0 IN Signal synchronized with commercial power source frequency.
This is the basic timing for time processing of LSI.
25 P41 OUT Terminal not used.
26 P40 IN Connected to GND through the pull-down resistor R100.
27
RESET
IN Auto clear terminal.
Signal is input to reset the LSI to the initial state when power is applied.
28-29 P71-P70 OUT Terminal not used.
30 XIN IN Internal clock oscillation frequency input setting.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit with
respect to XOUT terminal.
31 XOUT OUT Internal clock oscillation frequency control output.
Output to control oscillation input of XIN.
32 VSS IN Power source voltage: -5.0V.
VC voltage of power source circuit input.
33 P27 OUT Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P43-P46 terminal while one
of G8 line keys on key matrix is touched.
16.7 msec.
During cooking
H : GND
L : -5V
A
B
0.1 sec.
2.0 sec.
H : GND
L : -5V
H : GND
L : -5V
Maximum
output
70% of maximum
output
H : GND
L : -5V
H : GND
L : -5V
ON
ON
OFF
OFF OFF
24 sec.
8 sec.
Pin No. Signal I/O Description
16.7 msec.
H : GND
L : -5V