Service manual
32
R-1855A
DESCRIPTION OF LSI
LSI(IZA719DR)
The I/O signals of the LSI(IZA719DR) are detailed in the following table.
Pin No. Signal I/O Description
1 VCC IN Connected to GND.
2 VEE IN Anode (segment) of Fluorescent Display illumination voltage: -31V.
Vp voltage of power source circuit input.
3 AVSS IN Power source voltage:-5V.
VC voltage of power source circuit input.
4 VREF IN Reference voltage input terminal.
A reference voltage applied to the A/D converter in the LSI. Connected to GND.(0V)
5 AN7 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.
6 AN6 IN AH sensor input.
This input is an analog input terminal from the AH sensor circuit, and connected to the
A/D converter built into the LSI.
7-9 AN5-AN3 IN Heating constant compensation terminal.
10 AN2 IN Input signal which communicates the door open/close information to LSI.
Door closed; "L" level signal(0V).
Door opened; "H" level signal(-5V).
11 AN1 IN Signal coming from touch key.
When any one of G8 line keys on key matrix is touched, a corresponding signal will from
P00 - P06 will be input into AN1. When no key is touched, the signal is held at "L" level.
12 AN0 IN Temperature measurement input: OVEN THERMISTOR.
By inputting DC voltage corresponding to the temperature detected by the thermistor,
this input is converted into temoerature by the A/D converter built into the LSI.
13 P55 OUT Segment data signals.
The relation between signals and indicators are as follows:
Signal Segment Signal Segment
P13 ................... P16 P03 ..................... P8
P12 ................... P15 P02 ..................... P7
P11 ................... P14 P01 ..................... P6
P10 ................... P13 P00 ..................... P5
P07 ................... P12 P37 ..................... P4
P06 ................... P11 P36 ..................... P3
P05 ................... P10 P35 ..................... P2
P04 ..................... P9 P55 ..................... P1
(ß : INTO signal)
Refer to the touch control panel circuit about the relation between signals and
indicators. Normally, one pulse is output in every synchronized signal (ß) period, and
input to the anode of the fluorescent display.
14 P54 OUT Oven lamp driving signal. (Square Waveform : 60Hz)
To turn on and off the shut-off relay(RY1). The square
waveform voltage is delivered to the relay(RY1) driv-
ing circuit.
15 P53 OUT Turntable motor driving signal.
To turn on and off relay(RY4). "L" level: During
Turntable ON. "H" level: During Turntable OFF or
during the oven is off condition.
16 P52 OUT Cooling fan motor driving signal.
To turn on and off shut-off relay(RY5). "L" level during
both microwave and convection cooking; "H" level
otherwise.
17 P51 OUT Damper motor driving signal.
To turn on and off shut-off relay(RY6).
ß(60Hz)
GND
VP
During cooking
L
H
16.7 msec.
ON
OFF
During
cooking
L
GND
H.
ON
OFF
H : GND
L
ON
OFF
H : GND
L