Ambient Light Sensor IC Series Digital 16bit Serial Output Type Ambient Light Sensor IC No.11046EBT09 BH1751FVI Descriptions 2 BH1751FVI is an digital Ambient Light Sensor IC for I C bus interface. This IC is the most suitable to obtain the ambient light data for adjusting LCD and Keypad backlight power of Mobile phone. It is possible to detect wide range at High resolution. ( 1 - 65535 lx ). Features 1) I2C bus Interface (f / s Mode Support) 2) Spectral responsibility is approximately human eye response 3) Illuminance to Digital Converter 4) Wide range and High resolution. (1 - 65535 lx) 5) Low Current by power down function 6) 50Hz / 60Hz Light noise reject-function 7) 1.8V Logic input interface 8) No need any external parts 9) Light source dependency is little. (ex. Incandescent Lamp. Fluorescent Lamp. Halogen Lamp. White LED. Sun Light ) 10) It is possible to select 2 type of I2C slave-address. 11) Adjustable measurement result for influence of optical window ( It is possible to detect min. 0.11 lx, max. 100000 lx by using this function. ) 12) Small measurement variation (+/- 20%) 13) The influence of infrared is very small. 14) Build in power on reset circuit Applications Mobile phone, LCD TV, NOTE PC, Portable game machine, Digital camera, Digital video camera, PDA, LCD display Absolute Maximum Ratings Parameter Symbol Ratings Units Supply Voltage Vmax 4.5 V Operating Temperature Topr -4085 Storage Temperature Tstg -40100 SDA Sink Current Imax 7 mA Power Dissipation Pd 260 mW 70mm 70mm 1.6mm glass epoxy board. Derating in done at 3.47mW/ for operating above Ta=25. Operating Conditions Ratings Parameter Symbol Units Min. Typ. Max. VCC Voltage Vcc 2.4 3.0 3.6 V 2 I C Reference Voltage VDVI 1.65 - VCC V www.rohm.com 1/16 2011.11 - Rev.B 2011 ROHM Co., Ltd. All rights reserved. BH1751FVI Technical Note Electrical Characteristics ( VCC = 3.0V, DVI = 3.0V, Ta = 25, unless otherwise noted ) Limits Parameter Symbol Units Conditions Min. Typ. Max. 1 Supply Current Icc1 120 190 A Ev = 100 lx Powerdown Current Icc2 0.85 1.5 A No input Light Peak Wave Length p 560 nm Sensor out / Actual lx Measurement Accuracy S/A 0.96 1.2 1.44 times 1, 2 EV = 1000 lx 3 Dark ( 0 lx ) Sensor out S0 0 0 3 count H-Resolution Mode H-Resolution Mode Resolution rHR 1 lx L-Resolution Mode Resolution rLR 4 lx H-Resolution Mode tHR 120 180 ms Measurement Time L-Resolution Mode tLR 16 24 ms Measurement Time Incandescent / rIF 1 times EV = 1000 lx Fluorescent Sensor out ratio ADDR Input H Voltage VAH 0.7 * VCC V ADDR Input L Voltage VAL 0.3 * VCC V DVI Input L Voltage VDVL 0.4 V SCL, SDA Input H Voltage 1 VIH1 0.7 * DVI V DVI 1.8V SCL, SDA Input H Voltage 2 VIH2 1.26 V 1.65V DVI 1.8V SCL, SDA Input L Voltage 1 VIL1 0.3 * DVI V DVI 1.8V SCL, SDA Input L Voltage 2 VIL2 DVI 1.26 V 1.65V DVI 1.8V SCL, SDA, ADDR Input H Current IIH 10 A SCL, SDA, ADDR Input L Current IIL 10 A 2 I C SCL Clock Frequency fSCL 400 kHz 2 I C Bus Free Time tBUF 1.3 s 2 I C Hold Time ( repeated ) tHDSTA 0.6 s START Condition 2 I C Set up time tSUSTA 0.6 s for a Repeated START Condition 2 I C Set up time tSUSTD 0.6 s for a Repeated STOP Condition 2 I C Data Hold Time tHDDAT 0 0.9 s 2 I C Data Setup Time tSUDAT 100 ns 2 I C L Period of the SCL Clock tLOW 1.3 s 2 I C H Period of the SCL Clock tHIGH 0.6 s 2 I C SDA Output L Voltage VOL 0 0.4 V IOL = 3 mA 1 White LED is used as optical source. 2 Measurement Accuracy typical value is possible to change 1 byMeasurement result adjustment functio. 3 Use H-resolution mode or H-resolution mode2 if dark data ( less than 10 lx ) is need. www.rohm.com 2/16 2011.11 - Rev.B 2011 ROHM Co., Ltd. All rights reserved.