Ambient Light Sensor IC Series Digital 16bit Serial Output ...

1 Ambient Light Sensor IC Series Digital 16bit Serial Output Type Ambient Light Sensor IC. BH1750 FVI Descriptions 2. BH1750 FVI 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 2. 1) I C 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.

2 ( 1 - 65535 lx ). 5) Low Current by power down function 6) 50Hz / 60Hz Light noise reject-function 7) 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. lx, max. 100000 lx by using this function. ). 12) Small measurement variation (+/- 20%). 13) The influence of infrared is very small.

3 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 V. Operating Temperature Topr -40 85 . Storage Temperature Tstg -40 100 . SDA Sink Current Imax 7 mA. Power Dissipation Pd 260 mW. 70mm 70mm glass epoxy board. Derating in done at for operating above Ta=25 . Operating Conditions Ratings Parameter Symbol Units Min. Typ. Max. VCC Voltage Vcc V. I2C Reference Voltage VDVI - VCC V.

4 1/17 - 2011 ROHM Co., Ltd. All rights reserved. BH1750 FVI Technical Note Electrical Characteristics ( VCC = , DVI = , 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 A No input Light Peak Wave Length p 560 nm Sensor out / Actual lx Measurement Accuracy S/A times EV = 1000 lx 1, 2. 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 /.

5 RIF 1 times EV = 1000 lx Fluorescent Sensor out ratio ADDR Input H' Voltage VAH * VCC V. ADDR Input L' Voltage VAL * VCC V. DVI Input L' Voltage VDVL V. SCL, SDA Input H' Voltage 1 VIH1 * DVI V DVI SCL, SDA Input H' Voltage 2 VIH2 V DVI SCL, SDA Input L' Voltage 1 VIL1 * DVI V DVI SCL, SDA Input L' Voltage 2 VIL2 DVI V DVI SCL, SDA, ADDR. IIH 10 A. Input H' Current SCL, SDA, ADDR. IIL 10 A. Input L' Current I2C SCL Clock Frequency fSCL 400 kHz 2. I C Bus Free Time tBUF s 2. I C Hold Time ( repeated ). tHDSTA s START Condition I2C Set up time tSUSTA s for a Repeated START Condition I2C Set up time tSUSTD s for a Repeated STOP Condition I2C Data Hold Time tHDDAT 0 s I2C Data Setup Time tSUDAT 100 ns I2C L' Period of the SCL Clock tLOW s I2C H' Period of the SCL Clock tHIGH s I2C SDA Output L' Voltage VOL 0 V IOL = 3 mA.

6 1 White LED is used as optical source. 2 Measurement Accuracy typical value is possible to change '1' by "Measurement result adjustment function". 3 Use H-resolution mode or H-resolution mode2 if dark data ( less than 10 lx ) is need. 2/17 - 2011 ROHM Co., Ltd. All rights reserved. BH1750 FVI Technical Note Reference Data 64 100000. 56. 1. 10000. 48. Measurement Result Measurement Result 40. 1000. 32. Ratio H-Res. H-Res. L-Res. 24 100. 16. 10. 8 L-Res. 0 1. 0 0 8 16 24 32 40 48 56 64 1 10 100 1000 10000 100000. 400 500 600 700 800 900 1000 1100.

7 Illuminance [ lx ] Illuminance [ lx ]. Wavelength [ nm ]. Spectral Response Illuminance - Illuminance - Measurement Result 1 Measuremnet Result 2. 10. 1. 1. 8 . 1pin Measurement Result - +. 6. Ratio - Ratio 1pin - 4. - +. + 2. + H-Res. 0. 0 -90 -60 -30 0 30 60 90 0. -90 -60 -30 0 30 60 90 -40 -20 0 20 40 60 80 100. Angle [ deg ] Angle [ deg ]. Ta [ ]. Directional Characteristics 1 Directional Characteristics 2 Dark Response 200. Fluorescent Light 1. Incandescent ICC @ Measurement 150. Light Halogen Light Ratio 100. Kripton Light Artifical Sun 50.

8 Light White LED. 0 0. -40 -20 0 20 40 60 80 100 0 1 2 2 3 4. Ta [ ] Ratio VCC [ V ]. Measurement Accuracy Light Source Dependency VCC - ICC. Temperature Dependency ( Fluorescent Light is set to '1' ) ( During measurement ). 10. ICC @ POWER DOWN [ uA ]. 1 1. DVI= VCC=3V. 1. Ratio Ratio 0 0. -40 -20 0 20 40 60 80 100. 2 3 4 2 3 Ta [ ] VCC [ V ] DVI [ V ]. VCC ICC@0 Lx Measurement Result Measurement Result ( POWER DOWN ) VCC Dependency DVI Dependency 3/17 - 2011 ROHM Co., Ltd. All rights reserved. BH1750 FVI Technical Note Block Diagram VCC DVI.

9 Logic SCL. AMP ADC +. 2. I C Interface SDA. PD. OSC. GND ADDR. Block Diagram Descriptions PD. Photo diode with approximately human eye response. AMP. Integration-OPAMP for converting from PD current to Voltage. ADC. AD converter for obtainment Digital 16bit data. 2. Logic + I C Interface Ambient Light Calculation and I2C BUS Interface. It is including below register. Data Register This is for registration of Ambient Light Data. Initial Value is "0000_0000_0000_0000". Measurement Time Register This is for registration of measurement time.

10 Initial Value is "0100_0101". OSC. Internal Oscillator ( typ. 320kHz ). It is CLK for internal logic. Measurement Procedure Power supply Initial state is Power Down mode after State is automatically changed to VCC and DVI supply. Power Down mode. Power Down Power On Measurement Command One Time Measurement Continuous Measurement State Transition by I2C write-command. Automatically State Transition * "Power On" Command is possible to omit. 4/17 - 2011 ROHM Co., Ltd. All rights reserved. BH1750 FVI Technical Note Instruction Set Architecture Instruction Opecode Comments Power Down 0000_0000 No active state.