BR24G32-3A ROHM [Rohm], BR24G32-3A Datasheet - Page 18

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

●Software reset
●Acknowledge polling
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© 2012 ROHM Co., Ltd. All rights reserved.
BR24G32-3A
TSZ22111・15・001
Software reset is executed when to avoid malfunction after power on, and to reset during command input. Software reset
has several kinds, and 3 kinds of them are shown in the figure below. (Refer to Fig.41-(a), Fig.41-(b), Fig.41-(c).) In dummy
clock input area, release the SDA bus ('H' by pull up). In dummy clock area, ACK output and read data '0' (both 'L' level)
may be output from EEPROM, therefore, if 'H' is input forcibly, output may conflict and over current may flow, leading to
instantaneous power failure of system power source or influence upon devices.
During internal write execution, all input commands are ignored, therefore ACK is not sent back. During internal automatic
write execution after write cycle input, next command (slave address) is sent, and if the first ACK signal sends back 'L', then
it means end of write action, while if it sends back 'H', it means now in writing. By use of acknowledge polling, next
command can be executed without waiting for tWR = 5ms.
ACK signal sends back 'L', then execute word address input and data output and so forth.
When to write continuously, R/W = 0, when to carry out current read cycle after write, slave address R/W = 1 is sent, and if
SCL
SDA
SDA
SDA
SCL
SCL
SD
…
S
T
A
R
T
S
T
A
R
T
Write command
Fig.42 Case to continuously write by acknowledge polling
Fig.41-(b) The case of START + dummy clock × 9 +START+ command input
First write command
Fig.41-(a) The case of dummy clock × 14 +START+START+ command input
Slave
address
tWR
Start
1
A
C
K
H
1
Fig.41-(c) START×9+ command input
S
T
O
P
2
1
Dummy clock×14
2
S
T
A
R
T
Dummy clock×9
Start×9
2
3
Slave
address
S
T
A
R
T
Slave
address
タ
13
18/34
Second write command
A
C
K
L
※Start command from START input.
ト
14
8
After completion of internal write,
ACK=LOW is sent back, so input
next word address and data in
succession.
7
A
C
K
H
address
tWR
Word
9
During internal write,
ACK = HIGH is sent back.
8
Start×2
S
T
A
R
T
Start
Slave
address
A
C
K
L
9
Data
A
C
K
H
A
C
K
L
…
S
T
O
P
Normal command
Normal command
Normal command
Normal command
Normal command
Normal command
TSZ02201-0R2R0G100050 -1-2
15.May.2012 REV.001
Datasheet
Datasheet