Technical Note

BR25H□□□-WC series

9/19

www.rohm.com

2010.08 - Rev.D

© 2010 ROHM Co., Ltd. All rights reserved.

2. Read command (READ)

Product

number

Address

length

BR25H010-WC

A6-A0

BR25H020-WC

A7-A0

BR25H040-WC

A8-A0

Productnumber

Address

length

BR25H080-WC

A9-A0

BR25H160-WC

A10-A0

BR25H320-WC

A11-A0

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

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)

Product

number

Address

length

BR25H010-WC

A6-A0

BR25H020-WC

A7-A0

BR25H040-WC

A8-A0

Product

number

Address

length

BR25H080-WC

A9-A0

BR25H160-WC

A10-A0

BR25H320-WC

A11-A0

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

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

BR25H080/160/320-WC=Insignificant 5 bits

High-Z

12

1

1

0

0

3

7

1

2

D6

SO

CSB

SCK

SI

4

5

＊

A11

6

8

＊

＊

A0

A1

D7

23

30

24

D0

0

0

0

0

0

D2

D1

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

High-Z

1

1

0

0

3

7

1

2

D6

SO

CSB

SCK

SI

4

5

A4

6

8

A7

A0

A1

D7

15

22

16

D0

0

0

0

0

＊

1

D2

D1

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

9

10

11

A6

A5

*

1 BR25H010/020-WC=Don’t care

BR25H040-WC=A8

Fig.35 Read command (BR25H010/020/040-WC)

Fig.36 Read command (BR25H080/160/320-WC)

High-Z

23

D0

0

0

0

0

＊

1

D2

D1

D7

15

22

16

D6

0

A0

A1

1

1

2

4

0

CSB

SCK

SI

SO

0

3

7

8

5

6

A4

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

～ ～

A5

A6

A7

～ ～

～ ～

*1 BR25H010/020-WC=Don’t care

BR25H040-WC=A8

Fig.37 Write command (BR25H010/020/040-WC)

Fig.38 Write command (BR25H080/160/320-WC)

*=Don’t Care

High-Z

＊

=Don't Care

31

D0

0

0

0

0

0

D2

D1

D7

23

30

24

D6

0

A0

A1

＊

1

1

2

4

0

CSB

SCK

SI

SO

0

3

7

8

5

6

A11

～ ～

～ ～

～ ～

～ ～

～ ～

＊

＊

～ ～

～ ～

～ ～

～ ～

12

～ ～

～ ～

～ ～

～ ～

*1 BR25H010/020/040-WC=15 clocks

BR25H080/160/320-WC=23 clocks