BR24G32-3A ROHM [Rohm], BR24G32-3A Datasheet - Page 19

• Manufacturer Part Number: BR24G32-3A
• Description: High Reliability Serial EEPROMs I2C BUS BR24xxxxfamily
• Manufacturer: ROHM [Rohm]

●WP valid timing (write cancel)
●Command cancel by start condition and stop condition
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BR24G32-3A
TSZ22111・15・001
WP input in this area becomes don't care. The area from the rise of SCL to take in D0 to input the stop condition is cancel
valid area. And, after execution of forced end by WP, standby status gets in.
WP is usually fixed to 'H' or 'L', but when WP is used to cancel write cycle and so forth, pay attention to the following WP
valid timing. During write cycle execution, in cancel valid area, by setting WP='H', write cycle can be cancelled. In both byte
write cycle and page write cycle, the area from the first start condition of command to the rise of clock to taken in D0 of
data(in page write cycle, the first byte data) is cancel invalid area.
During command input, by continuously inputting start condition and stop condition, command can be cancelled. (Fig.44)
However, in ACK output area and during data read, SDA bus may output 'L', and in this case, start condition and stop
condition cannot be input, so reset is not available. Therefore, execute software reset. And when command is cancelled by
start, stop condition, during random read cycle, sequential read cycle, or current read cycle, internal setting address is not
determined, therefore, it is not possible to carry out current read cycle in succession. When to carry out read cycle in
succession, carry out random read cycle.
SDA
WP
SDA
SCL
S
T
A
R
T
・
SDA
SCL
Rise of D0 taken clock
address
Sl a ve
Fig.44 Case of cancel by start, stop condition during slave address input
C
A
K
L
Enlarged view
address
WP cancel invalid area
Word
D1
A
C
K
L
D0
1
D7 D6 D5 D4 D3 D2 D1 D0
ACK
Fig.43 WP valid timing
0
1
19/34
Data is not written.
WP cancel valid area
A
C
K
L
0
SCL
SDA
Data
Start condition
Enlarged view
D0
・Rise of SDA
C
A
K
L
ACK
S
O
P
T
WP cancel invalid area
Stop condition
TSZ02201-0R2R0G100050 -1-2
tWR
15.May.2012 REV.001
Datasheet
Datasheet