Sharp R-990KS Service Manual page 21

Pin No. Signal I/O
13 P55 OUT
14 P54 OUT
15 P53 OUT
16 P52 OUT
17 P51 OUT
18 P50 OUT
19 P47 OUT
20-21 P46-P45 OUT
22 P44 OUT
23 P43 OUT
24 P42 OUT
Digit selection signal.
The relationship between digit signal and digit are as fol-
lows;
Digit signal Digit
P02..........................2nd.
P03...........................1st.
P01...........................3rd.
P00...........................4th.
P37...........................5th.
P36.......................... 6th.
P35.......................... 7th.
P55.......................... 8th.
Normally, one pulse is out put in every speriod, and input to
the grid of the Fluorescent Display.
Oven lamp and turntable motor driving signal. (Square Waveform : 50Hz)
To turn on and off the shut-off relay(RY1). The square waveform volt-
age is delivered to the relay(RY1) driving circuit.
Convection motor driving signal.
To turn on and off shut-off relay(RY5). "L" level during CONVECTION;
"H" level otherwise.
Cooling fan motor driving signal.
To turn on and off shut-off relay(RY6). "L" level during both micro-
wave and convection cooking; "H" level otherwise.
Magnetron high-voltage circuit driving signal.
To turn on and off the cook relay(RY2). In HIGH opera-
tion, the signals holds "L" level during microwave cook-
ing and "H" level while not cooking. In other cooking
modes (MED HIGH, MED, MED LOW, LOW) the signal
turns to "H" level and "L" level in repetition according to
the power level.
Damper motor relay driving signal.
To turn on and off shut-off relay(RY4).
Heating element driving signal.
To turn on and off shut-off relay(RY3). "L" level during convection cook-
ing; "H" level otherwise. During convection cooking, the signal
becomes "H" level when the temperature of the oven cavity exceeds
the predetermined temperature.
Terminal not used.
Timing signal output terminal for temperature measurement(OVEN THERMISTOR).
H level (GND) : Thermistor OPEN timing.
L level (-5V) : Temperature measuring timing.(Convection cooking)
Signal to sound buzzer.
A: key touch sound.
B: Completion sound.
C: When the temperature of the oven cavity reaches the preset
temperature in the preheating mode, or when the preheating
hold time (30 minutes) is elapsed.
Timing signal output terminal for temperature measurement(OVEN).
H level (GND) : Thermistor OPEN timing.
L level (-5V) : Temperature measuring timing.(Convection cooking)
Description
ß(50Hz)
P 03
P 02
P 01
P 00
P 37
P 36
P 35
P 55
VARI MODE
HIGH (100% power)
MED HIGH (approx. 70% power)
MED (approx. 50% power)
MED LOW (approx. 30% power)
LOW (approx. 10% power)
9 – 2
R990K(W)
G ND
V P
20 ms ec.
During cooking
During
OFF
cooking
(Convection)
ON
OF F
During
cooking
ON
ON TIME OFF TIME
32 sec.
24 sec.
18 sec.
12 sec.
6 sec.
OF F
ON
During
OF F
cooking
(C onvection)
ON
0.12 s ec
A
2.4 s ec
B
1.2 s ec
1.2 s ec
C
H
L
H
L
H. GND
L
H. G ND
L
0 sec.
8 sec.
14 sec.
20 sec.
26 sec.
H : G ND
L
H.
G ND
L
H: G ND
L