S-24C08C Datasheet, PDF (14/33 Pages) Seiko Instruments Inc – Write protect function during the low power supply voltage

2-WIRE SERIAL E²PROM
S-24C08C (WLP PRODUCT)
Rev.1.0_00_H
6. 3 Write protect
Write protect is available in the S-24C08C. When the WP pin is connected to the V_CC, write operation to memory
area is inhibited.
When the WP pin is connected to GND or set in open, the write protect is invalid, and write operation in all
memory area is available.
Fix the level of the WP pin from start condition in the write operation (byte write, page write) until stop condition. If
the WP pin changes during this time, the address data being written at this time is not guaranteed. Regarding the
timing of write protect, refer to Figure 5.
In not using the write protect, connect the WP pin to GND or set it open. The write protect is valid in the range of
operation power supply voltage.
As seen in Figure 13 when the write protect is valid, the S-24C08C does not generate an acknowledgment signal
after data input.
S
W
T
R
A
I
R
T
DEVICE
ADDRESS
T
E
WORD ADDRESS
S
T
O
DATA
P
SDA LINE
1 0 1 0 _{A2 P1 P0} 0 _{W7 W6 W5 W4 W3 W2 W1 W0 D7 D6 D5 D4 D3 D2 D1 D0}
M
LR A
S
S/ C
B
BW K
A_A
C_C
K_K
N
A
C
K
WP
Figure 13 Write Protect
14