Technical Note
BR25H□□□-WC series
2. Read command (READ)
CSB
~~
~~
~~
~~
Product
number
BR25H010-WC
BR25H020-WC
BR25H040-WC
Address
length
A6-A0
A7-A0
A8-A0
0
1
2
3
4
5
6
7
8
9
10
11
15
16
22
SCK
SI
~~
0
0
0
0
*1
0
1
1
A7 A6 A5
A4
A1 A0
~~
~~
~~
~~
High-Z
D7 D6
D2 D1 D0
SO
*1 BR25H010/020-WC=Don’t care
BR25H040-WC=A8
Fig.35 Read command (BR25H010/020/040-WC)
CSB
SCK
~
~
~~
~~
~~
Productnumber
Address
length
A9-A0
A10-A0
A11-A0
~~
0
1
2
3
4
5
6
7
8
12
23
24
30
~~
BR25H080-WC
BR25H160-WC
BR25H320-WC
~~
~~
*
*
*
0
0
0
0
0
0
1
1
A11
A1 A0
~~
SI
~~
~~
~~
~~
~~
High-Z
D7 D6
D2 D1 D0
SO
*=Don’t Care
*1 BR25H010/020/040-WC=15 clocks
BR25H080/160/320-WC=23 clocks
Fig.36 Read command (BR25H080/160/320-WC)
By read command, data of EEPROM can be read. As for this command, set CSB LOW, then input address after read ope
code. EEPROM starts data output of the designated address. Data output is started from SCK fall of 15/23*1 clock, and
from D7 to D0 sequentially. This IC has increment read function. After output of data for 1 byte (8bits), by continuing input
of SCK, data of the next address can be read. Increment read can read all the addresses of EEPROM. After reading data
of the most significant address, by continuing increment read, data of the most insignificant address is read.
3. Write command (WRITE)
CSB
~~
~~
~~
~~
Product
number
BR25H010-WC
BR25H020-WC
BR25H040-WC
Address
length
A6-A0
A7-A0
A8-A0
0
1
2
3
4
5
6
7
8
15
16
22
23
SCK
~~
~~
~~
0
0
0
0
*1
0
1
0
A7
A6
A5
A4
A1
A0
D7 D6
D2
~~
D1
D0
SI
~~
~~
High-Z
SO
*1 BR25H010/020-WC=Don’t care
BR25H040-WC=A8
Fig.37 Write command (BR25H010/020/040-WC)
Product
number
BR25H080-WC
BR25H160-WC
BR25H320-WC
Address
length
A9-A0
A10-A0
A11-A0
CSB
SCK
~~
~~
~~
~~
~~
~~
0
1
2
3
4
5
6
7
8
12
23
24
30
31
~~
~~
~~
*
*
*
0
0
0
0
0
0
1
0
A11
A1
A0
D7 D6
D2
~~
D1
D0
SI
~~
High-Z
~~
~~
SO
*=Don't Care
Fig.38 Write command (BR25H080/160/320-WC)
By write command, data of EEPROM can be written. As for this command, set CSB LOW, then input address and data
after write ope code. Then, by making CSB HIGH, the EEPROM starts writing. The write time of EEPROM requires time of
tE/W (Max 5ms). During tE/W, other than status read command is not accepted. Start CSB after taking the last data (D0),
and before the next SCK clock starts. At other timing, write command is not executed, and this write command is
cancelled. This IC has page write function, and after input of data for 1 byte (8 bits), by continuing data input without
starting CSB, data up to 16/32*1bytes can be written for one tE/W. In page write, the insignificant 4/5*2 bit of the designated
address is incremented internally at every time when data of 1 byte is input and data is written to respective addresses.
When data of the maximum bytes or higher is input, address rolls over, and previously input data is overwritten.
*1 BR25H010/020/040-WC=16 bytes at maximum
BR25H080/160/320-WC=32 bytes at maximum
*2 BR25H010/020/040-WC=Insignificant 4 bits
BR25H080/160/320-WC=Insignificant 5 bits
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2010.08 - Rev.D
9/19