BU9844GUL-W_10 Datasheet, PDF (9/19 Pages) Rohm – WL-CSP EEPROM family I2C BUS

BU9844GUL-W
Technical Note
○Notes on write cycle continuous input
SDA
LINE
S
W
T
R
A
R
T
SLAVE
ADDRESS
I
T
E
WORD
ADDRESS(n)
DATA(n)
S
T
DATA(n+15)
O
P
1 0 1 0 P2P1P0 ^WA
7
RA
/C
WK
WA
0
D7
A
C
K
D0
A
C
K
D0
A
C
K
Fig.37 Page write cycle
At STOP (stop bit),
Write starts.
S
T
A
R
T
1 0 10
Next command
tWR (maximum : 5ms)
Command is not accepted for this period.
Note)
1 0 1 0 P2 P1 P0
Fig.38 Difference of each type of slave address
○Notes on page write cycle
○Internal address increment Page write mode
List of numbers of page write
Number of Pages
16Byte
Product number
BU9844GUL-W
WA7 ----- WA4 WA3
0 ----- 0
0
0 ----- 0
0
0 ----- 0
0
WA2
0
0
0
WA1
0
0
0
WA0
0
0
0
Increment
The above numbers are maximum bytes for respective types.
Any types below these can be written.
0Eh
0
0
-----
-----
0
0
1page = 16 bytes, but the page write cycle write time is 5ms at maximum
for 16byte bulk write.
It does not stand 5ms at maximum x 16 bytes = 80ms (Max.).
0 ----- 0
1
1
1
0
1
1
1
1
0
0
0
0
Significant bit is fixed.
No digit up
For example, when it is started from address 0Eh,
therefore, increment is made as below,
0Eh→0Fh→00h→01h ---, which please note.
*0Eh --- 0E in hexadecimal, therefore, 00001110
○Write protect terminal (WP)
becomes a binary number.
・Write protect function
When WP terminal is set Vcc (H level), data rewrite of all addresses is prohibited. When it is set GND (L level), data
rewrite of all addresses is enabled. Be sure to connect this terminal to Vcc or GND, or control it to H level or L level. Do
not use it open.
At extremely low voltage at power ON/OFF, by setting the WP terminal “H”, mistake write can be prevented.
During tWR, set the WP terminal always to “L”. If it is set “H”, write is forcibly terminated.
www.rohm.com
© 2010 ROHM Co., Ltd. All rights reserved.
9/18
2010.09 - Rev.A