Sharp R-310EK, Service Manual

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19
R-310EK
R-310EW
11 P57 OUT Back light circuit (Light emitting diodes) driving signal.
12-13 P56-P55 OUT Terminal not used.
14 CNTR0 OUT Signal to sound buzzer (2.0 kHz).
A: key touch sound.
B: Completion sound.
15 P53 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.
16 P52 OUT Magnetron high-voltage circuit driving signal.
To turn on and off the cook relay (RY2). The
signals holds "L" level during microwave cook-
ing 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.
(ON and OFF times for other power level.)
17-18 P51-P50 OUT Terminal not used.
19-20 P47-P46 OUT Terminal not used.
21 P45 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 P45. When no key is touched, the signal is held at "H" level.
22 P44 IN Signal similar to P45.
When either G11 line on key matrix is touched, a corresponding signal will be input into P44.
23 P43 IN Signal similar to P45.
When either G10 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 IN Signal similar to P45.
When either G9 line on key matrix is touched, a corresponding signal will be input into P41.
26 P40 IN Connected to GND through the pull-down resistor R90.
27 RESET IN Auto clear terminal.
Signal is input to reset the LSI to the initial state when power is applied. Temporarily set
"L" level the moment power is applied, at this time the LSI is reset. Thereafter set at "H"
level.
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 XIN terminal.
31 XOUT OUT Internal clock oscillation frequency control output.
Output to control oscillation input of XOUT.
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 P41, P43, P44 and P45
terminal while one of G8 line keys on key matrix is touched.
Pin No. Signal I/O Description
A
B
0.1 sec.
2.0 sec.
H : GND
L : -5V
H : GND
L : -5V
16.7 msec.
During cooking
H : GND
L : -5V
P-HI
H : GND
L : -5V
H : GND
L : -5V
P-70
ON
ON
OFF
OFF OFF
24 sec.
8 sec.
16.7 msec.
H : GND
L : -5V