Description Of Lsi - Sharp R-820BK Service Manual

LSI(IZA888DR)
The I/O signal of the LSI(IZA888DR) are detailed in the following table.
Pin No. Signal
1 C1
2 VL1
3-5 AN7-AN5
6 AN4
7 AN3
8 AN2
9-10 AN1-AN0
11 P57
12 P56
13 P55
14-18 P54-P50 IN/OUT
19 P47
20 P46
21 P45
22 P44
23 INT1
24 INT0
25 P41

DESCRIPTION OF LSI

I/O
IN Terminal not used.
IN Power source voltage input terminal.
Standard voltage for LCD.
IN Heating constant compensation terminal.
IN Terminal not used.
IN Temperature measurement input: OVEN THERMISTOR.
By inputting DC voltage corresponding to the temperature detected by the thermistor,
this input is converted into temperature by the A/D converter built into the LSI.
IN Input signal which communicates the door open/close information to LSI.
Door closed; "H" level signal.
Door opened; "L" level signal.
IN Terminal not used.
OUT Timing signal output terminal for temperature measurement(OVEN THERMIS-
TOR).
"H" level (GND) : Thermistor OPEN timing.
"L" level (-5V) : Temperature measuring timing. (Convection cooking)
OUT Signal to sound buzzer.
A: key touch sound.
B: Completion sound.
C: When the temperature of the oven cav-
ity reaches the preset temperature in
the preheating mode, or when the
preheating hold time (30 minutes) is
elapsed.
OUT Timing signal output terminal for temperature measurement(OVEN THERMIS-
TOR).
"H" level (GND) : Thermistor OPEN timing.
"L" level (-5V) : Temperature measuring timing. (Convection cooking)
Terminal not used.
IN Signal coming from touch key.
When any one of G12 line keys on key matrix is touched, a corresponding signal from
P40, P41, P72, P73, P74, P75, P76 and P77 will be input into P47. When no key is
touched, the signal is held at "L" level.
IN Signal similar to P47.
When any one of G11 line keys on key matrix is touched, a corresponding signal will
be input into P46.
IN Signal similar to P47.
When any one of G10 line keys on key matrix is touched, a corresponding signal will
be input into P45.
IN Signal similar to P47.
When any one of G9 line keys on key matrix is touched, a corresponding signal will
be input into P44.
IN Terminal not used.
IN Signal to synchronized LSI with commercial power source frequency(60Hz).
This is basic timing for time processing of LSI.
OUT Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P44 - P47 terminal while
one of G8 line key on matrix is touched.
Description
25
0.1 sec
A
2.0 sec
B
1.0 sec
1.0 sec
H: GND
C
L
H : GND
L (-5V)
16.7 msec.
R-820BK
R-820BW