
BH1751FVI
● Application circuit example
I 2 C bus pull up resister
Technical Note
BH1751FVI
VCC
SCL
2.2kohm
2.2kohm
I 2 C bus voltage source
0.1μF
ADDR
GND
DVI
SDA
0.1μF
Micro
Controller
* I 2 C BUS is trademark of Phillips Semiconductors. Please refer formality specification for pull up resister.
● Caution of power on reset function
BH1751FVI has power on reset (POR) function. POR is to reset all register and flip flop when VCC Power supplies.
There are some cautions about power on and down sequence seeing in below.
①
②
Power on time : t1
More than 2ms is need to active BH1751FVI after VCC supplies more than 2.0V from VCC is less than 0.4V.
Power off time : t2
More than 1ms (VCC < 0.4V) is need to active BH1751FVI.
2.0V
VCC
0.4V
BH1751FVI
t1
t2
t1
Don’t care
active
Don’t care
active
*”active state” is that BH1751FVI works and accept I 2 C bus access correctly.
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2011.11 - Rev.B