Toshiba 4580, Service Manual

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6570/5570 ADF 16 - 44 Mar. 1999 © TOSHIBA TEC
16.10.7 EEPROM circuit diagram
This circuit comprises an EEPROM for storing ADF data and other peripheral circuits.
IC11 is memory for storing the adjustment values of reflection-type sensors. Data transactions with the
CPU are performed on a 4-lead type serial interface. Once data is stored, it is held in memory and does
not disappear even when the power is turned OFF.
Pin 1 (CS) of IC11 is the chip select terminal, and is High when data transactions are in progress.
Pin 2 (CLK) of IC11 is the serial clock terminal, and is sent synchronized with the clock that is input to this
terminal.
Pin 3 (DI) of IC11 is the serial data input terminal, and pin 4 (DO) is the serial data output terminal.
IC11 is powered by +5V from E2PROM. IC11 power is held by D11, R74 and C42 until writing of data is
completed even if something causes the power voltage to fall during writing of data.
RA2.4
+5V
5V
+5V
IC11
4
1
2
3
2
2
7
6
1
1
C42
D0
CS
CLK
DI
R74
D11
7
2
1
8
D10
R75
K
A
RA2.1
2
1
RA2.2
4
3
RA2.3
6
5
RA1.1
2
2
1
RA1.4
8
RA1.3
6
RA1.2
4
1
7
5
3
SGND
1
+
2
DO
CS
CLK
DI
NC2
NC1
K
A
SGND