Service manual

19
R-300BW
Pin No. Signal I/O Description
ON/OFF time ratio in Micro
cooking
(a. 32second time base)
MICRO ON OFF
COOK
100% 32sec. 0sec.
70% 24sec. 8sec.
50% 18sec. 14sec.
30% 12sec. 20sec.
10% 6sec. 26sec.
16.7 msec
During cooking
H
L
16.7 msec
H : GND
L (-5V)
A
H: GND
L: -5V
2.0 sec
23 D6 OUT Magnetron high-voltage circuit driving signal.
To turn on and off the cook relay (RY2). In 100%
POWER operation, the signals hold "L" level
during microwave cooking and "H" level while
not cooking. In other cooking modes (70%, 50%,
30%, 10%) the signal turns to "H" level and "L"
level in repetition according to the power level.
24 D7 IN/OUT Terminal not used.
25 D8 OUT
Oven lamp, turntable motor and fan motor driving signal(Square Waveform : 60Hz).
To turn on and off shut-off relay (RY1).
The square waveform voltage is deliv-
ered to the relay (RY1) driving circuit and
relay(RY2) control circuit.
26 NC No connection terminal.
27 F0 IN
Input signal which communicates the door open/close information to LSI.
Door closed; "H" level signal.
Door opened; "L" level signal.
28 F1 Terminal not used.
29 F2 IN
Signal to synchronize LSI with commercial power source frequency.
This is basic timing for all real time processing of
LSI.
30 F3 IN Signal coming from encoder.
Signal similar to INT. Pulse signals are input into F3.
31-32 NC No connection terminal.
33 XOUT OUT
Internal clock oscillation frequency control output.
Output to control oscillation input of XOUT.
34 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.
35 CNTR OUT
Signal to sound buzzer.
A: Completion sound.
36 VDD IN Power source voltage: 0V.
The power source voltage to drive the LSI is input to VDD terminal.