Technical Note

8/21

BR24T□□□□Series

www.rohm.com

2011.03 - Rev.A

© 2011 ROHM Co., Ltd. All rights reserved.

●Write Command

○Write cycle

・Arbitrary data is written to EEPROM. When to write only 1 byte, byte write is normally used, and when to write

continuous data of 2 bytes or more, simultaneous write is possible by page write cycle. The maximum number of write

bytes is specified per device of each capacity. Up to 256 arbitrary bytes can be written.(In the case of BR24T1M-W)

W

R

I

T

E

S

T

A

R

T

R

/

W

A

C

K

S

T

O

P

WO R D

ADD R ESS(n )

DAT A (n)

SDA

LIN E

A

C

K

A

C

K

D A T A (n+ 15)

A

C

K

SL AVE

ADDR E SS

1 0

0

1A 0

A1

A2

WA

7

D0

D7

D 0

注 )

WA

0

A1

A2

WA

7

D7

1

1

0

0

W

R

I

T

E

S

T

A

R

T

R

/

W

S

T

O

P

WORD

ADDRESS

DATA

SLAVE

ADDRESS

A0

WA

0

D0

A

C

K

SDA

LINE

A

C

K

A

C

K

Note)

(BR24T01/02/04/08/16-W)

A1

A2

WA

14

1

1

0

0

W

R

I

T

E

S

T

A

R

T

R

/

W

S

T

O

P

1st WORD

ADDRESS

DATA

SLAVE

ADDRESS

A0

D0

A

C

K

SDA

LINE

A

C

K

A

C

K

Note)

WA

13

WA

12

WA

11

WA

0

A

C

K

2nd WORD

ADDRESS

D7

*1

WA

15

*1

As for WA12, BR24T32-W becomes Don't care.

As for WA13, BR24T32/64-W becomes Don't care.

As for WA14, BR24T32/64/128-W becomes Don't care.

As for WA15, BR24T32/64/128/256-W becomes Don't care.

(BR24T32/64/128/256/512/1M-W)

(BR24T01/02/04/08/16-W)

(BR24T32/64/128/256/512/1M-W)

*1

As for WA12, BR24T32-W becomes Don't care.

As for WA13, BR24T32/64-W becomes Don't care.

As for WA14, BR24T32/64/128-W becomes Don't care.

As for WA15, BR24T32/64/128/256-W becomes Don't care.

*2

As for BR24T128/256-W becomes (n+63)

As for BR24T512-W becomes (n+127)

As for BR24T1M-W becomes (n+255)

W

R

I

T

E

S

T

A

R

T

R

/

W

A

C

K

S

T

O

P

1st WORD

ADDRESS(n)

SDA

LINE

A

C

K

A

C

K

DATA(n+31)

A

C

K

SLAVE

ADDRESS

1

0

0

0

1

0

A0

A1

A2

WA

14

D0

注 )

*1

DATA(n)

D0

D7

A

C

K

2nd WORD

ADDRESS(n)

WA

0

WA

13

WA

12

WA

11

*2

Note)

Fig.42 Difference of slave address of each type

*1

*2

*2

*1

WA

15

*1

In BR24T16-W, A2 becomes P2.

*2

In BR24T08/16-W, A1 becomes P1.

*3

In BR24T04/08/16/1M-W A0 becomes P0.

1 0

0

1A 0

A1

A2

*1 *2 *3