BU99901GUZ-W_10 Datasheet, PDF (9/17 Pages) Rohm – WL-CSP EEPROM family I2C BUS

BU99901GUZ-W
Technical Note
○Notes on write cycle continuous input
SDA
L INE
S
T
A
R
T
SLAVE
ADDRESS
W
R
I
T
E
WORD
ADDRESS (n)
DATA (n)
DATA (n+31)
At STOP (stop bit)
write starts.
S
T
O
P
S
T
A
R
T
1 0 1 0 P2 P1P0
WA
7
RA
/C
WK
WA _D7
0
A
C
K
D0
A
C
K
Fig.37 Page write cycle
D0
A
C
K
1 0 10
Next command
tWR (maximum :5ms)
Command is not ac cepted for this period.
○Notes on page write cycle
List of numbers of page write
Number of pages
32Byte
Product number BU99901GUZ-W
○Internal address increment
Page write mode
WA11 ----- WA5
0 ----- 0
0 ----- 0
0 ----- 0
WA4
0
0
0
WA3
0
0
0
WA2
0
0
0
WA1
0
0
1
WA0
0
1
0
increment
The above numbers are maximum bytes for respective types.
Any bytes below these can be written.
In the case of BU99901GUZ-W, 1 page = 32bytes,
but the page write cycle write time is 5ms at maximum
for 32byte bulk write.
0
IEh
0
0
It does not stand 5ms at maximum × 32byte = 160ms(Max.).
----- 0
1
1
1
----- 0
1
1
1
----- 0
0
0
0
Significant bit is fixed.
No digit up
1
0
1
1
0
0
For example, when it is started from address 1Eh,
therefore, increment is made as below,
1Eh→1Fh→00h→01h･･･, which please note.
* 1Eh･･･16 in hexadecimal,
therefore, 00011110 becomes a binary number.
○Write protect (WP) terminal
・Write protect (WP) function
When WP terminal is set Vcc (H level), data rewrite of all address is prohibited. When it is set GND (L level),
data rewrite of all address 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
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9/16
2010.09 - Rev.A