BH1771GLC-E2

Ambient Light Sensor ICs 1 Chip Optical Proximity Sensor + Ambient Light Sensor IC BH1771GLC No.11046EBT11 ●Descriptions BH1771GLC is the IC into which optical proximity sensor and digital ambient light senor are unified. Proximity sensor part detects the human or object approach by reflection of infrared LED(IrLED) light. And this device can drive maximum 3 IrLEDs, and touch-less motion detection function can be implemented. Ambient light part can detect the wide range illuminance from the dark up to under direct sun light. The illuminant intensity of LCD display and keypad can be adjusted, so lower current consumption or higher visibility are possible. ●Features 2 1) Correspond to I C bus interface ( f/s mode & Hs mode support ) 2) Low Current by power down function 3) Correspond to 1.8V logic interface 4) ALS spectral responsibility is approximately human eye response ( Peak wavelength : typ. 550nm ) 5) Correspond to wide range of light intensity ( 1-65535 lx range ) 6) Rejecting 50Hz/60Hz light noise (ALS function) 2 7) Detection range of proximity sensor is around 10 - 100mm (configurable by I C bus) 8) Touch-less motion detection function 9) Built in ambient light cancelation (Proximity sensor function) 10) Built in configurable IrLED current driver ●Applications Mobile phone, DSC, Portable game, Camcoder, Car navigation, PDA, LCD display etc. ●Absolute Maximum Ratings ( Ta = 25℃ ) Parameter Symbol Ratings Units Vccmax 4.5 V VSDAmax, VSCLmax, VGNDNCmax 4.5 V VLEDmax, VINTmax 7 V Operating Temperature Topr -40～85 ℃ Storage Temperature Tstg -40～100 ℃ SDA, INT Sink Current Imax 7 mA Pd 250※ mW VCC, Supply Voltage SDA,SCL,GNDNC Terminal Voltage LED1,LED2,LED3 INT Terminal Voltage Power Dissipation ※ 70mm × 70mm × 1.6mm glass epoxy board. Decreasing rate is 3.33mW/℃ for operating above Ta=25℃ ●Operating Conditions Parameter Symbol Ratings Min. Typ. Max. Units VCC Voltage Vcc 2.3 2.5 3.6 V LED1,LED2,LED3 Terminal Voltage Vled 0.7 2.5 5.5 V www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 1/32 2011.06 - Rev.B BH1771GLC Technical Note ●Electrical characteristics ( VCC = 2.5V, Ta = 25℃, unless otherwise noted. ) Parameter Supply current for ALS Symbol Icc1 Limits Min. Typ. 90 － Max. 180 Units Conditions μA Ev = 100 lx ※1 Average current when ALS_CONTROL register(40h) = ” 03h ” and the other registers are default. Average current when PS_CONTROL register(41h) = ” 03h ” and the other registers are default. Supply current for PS Icc2 － 90 180 μA Supply current for PS during driving LED current Icc3 － 6.5 8.5 mA Standby mode current Icc4 － 0.8 1.5 μA ALS & PS standby No Input Light f/s mode tMALS － 100 125 ms H-Resolution mode ALS measurement accuracy S/A 0.85 1.0 1.15 Times Sensor out / Actual lx, Ev = 1000 lx ※1 ALS dark ( 0 lx ) sensor out ALS0 0 0 2 count H-Resolution mode PS sensor out (No proximity object) PS0 0 0 9 count Ambient irradiance = 2 0μW/cm PS sensor out ( Irradiance by proximity object = 324μW/cm2) PS324u 120 128 136 count Ambient irradiance = 0μW/cm2 ILED pulse duration twILED － 200 250 μs Cumulative ILED pulse duration twILED2 － 1 1.25 ms PS measurement time tMPS － 10 12.5 ms LED1 terminal sink current at LED1 terminal voltage = 1.3V ILED1 18 20 22 mA ILED register(42h) [2:0] = ” 010 ” LED2 terminal sink current at LED2 terminal voltage = 1.3V ILED2 18 20 22 mA ILED register(42h) [5:3] = ” 010 ” LED3 terminal sink current at LED3 terminal voltage = 1.3V ILED3 18 20 22 mA ILED3 register(43h) [2:0] = ” 010 ” INT output ‘L’ Voltage VINT 0 － 0.4 V SCL SDA input 'H' Voltage VIH 1.26 － － V SCL SDA input ‘L’ Voltage VIL － － 0.54 V SCL SDA input 'H'/’L’ Current IIHL -10 － 10 μA I2C SDA output ‘L’ Voltage VOL 0 － 0.4 V ALS measurement time ※1 ILED register(42h) [7:6] = ”11” IINT = 3mA IOL = 3mA White LED is used as optical source www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 2/32 2011.06 - Rev.B BH1771GLC Technical Note ●I2C bus timing characteristics ( VCC = 2.5V, Ta = 25℃, unless otherwise noted. ) Parameter Symbol Limits Min. Typ. Max. Units Conditions I2C SCL Clock Frequency fSCL 0 － 400 kHz f/s mode I2C SCL Clock Frequency2 fSCLH 0 － 3.4 MHz Hs mode Cb=100pF I2C Hold Time ( Repeated ) START Condition tHD;STA 0.6 － － μs f/s mode I2C Hold Time ( Repeated ) START Condition2 tHD;STA 160 － － ns Hs mode I2C ‘L’ Period of the SCL Clock tLOW 1.3 － － μs f/s mode I2C ‘L’ Period of the SCL Clock2 tLOW 160 － － ns Hs mode I2C 'H' Period of the SCL Clock tHIGH 0.6 － － μs f/s mode I2C 'H' Period of the SCL Clock2 tHIGH 60 － － ns Hs mode I2C Set up time for a Repeated START Condition tSU;STA 0.6 － － μs f/s mode I2C Set up time for a Repeated START Condition2 tSU;STA 160 － － ns Hs mode I2C Data Hold Time tHD;DAT 0 － － μs f/s mode I2C Data Hold Time2 tHD;DAT 0 － 70 ns Hs mode Cb=100pF I2C Data Setup Time tSU;DAT 100 － － ns f/s mode I2C Data Setup Time2 tSU;DAT 10 － － ns Hs mode I2C Set up Time for STOP Condition tSU;STO 0.6 － － μs f/s mode I2C Set up Time for STOP Condition2 tSU;STO 160 － － ns Hs mode I2C Bus Free Time between a STOP and START Condition tBUF 1.3 － － μs I2C Data Valid Time tVD;DAT － － 0.9 μs f/s mode I2C Data Valid Acknowledge Time tVD;ACK － － 0.9 μs f/s mode www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 3/32 2011.06 - Rev.B BH1771GLC Technical Note ●Package outlines A B Production code Lot No. WLGA010V28 www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 4/32 2011.06 - Rev.B BH1771GLC Technical Note ●Reference Data 56 1.0 0.6 0.4 0.2 48 Measurement Result Measurement Result 10000 0.8 Ratio 100000 64 1.2 40 32 24 16 1000 100 10 8 1 0 0.0 400 500 600 700 800 900 1000 0 1100 8 16 24 32 40 48 56 1 64 10 100 Wavelength [ nm ] 1.2 1.2 1 1 10000 100000 Fig.3 Illuminance ALS Measurement Result 2 Fig.2 Illuminance ALS Measurement Result Fig.1 ALS Spectral Response 1000 Illuminance [ lx ] Illuminance [ lx ] 10 1pin 0.6 0.4 - 0.6 1pin - 0.4 + - + 0.2 0.2 0 -90 -60 -30 0 Measurement Result 8 0.8 + - Ratio Ratio 0.8 30 60 2 + -90 -60 -30 0 30 60 0 90 -40 Fig.5 ALS Directional Characteristics 2 Ratio Halogen Light 0.6 Kripton Light 0.4 Artifical Sun Light 0.2 White LED 60 80 60 80 100 150 100 50 0 0 0 40 Fig.6 ALS Dark Response ICC @ Measurement [ uA ] Incandescent Light 0.8 40 20 200 Fluorescent Light 1 20 0 Ta [ ℃ ] 1.2 0 -20 Angle [ deg ] Fig.4 ALS Directional Characteristics 1 -20 4 0 90 Angle [ deg ] -40 蛍光灯白熱灯感度比 6 0.5 1 1.5 Ratio 2 2 2.5 3 VCC [ V ] 3.5 4 100 Ta [ ℃ ] Fig.7 ALS Measurement Accuracy Temperature Dependency 1.2 1 1.20 1.2 1.00 1 0.80 0.8 Ratio 0.6 Ratio 1pin 0.8 Ratio Fig.9 VCC - ICC ( During ALS measurement ) Fig.8 ALS Light Source Dependency ( Fluorescent Light is set to '1' ) 0.60 0.4 0.2 2.4 2.6 2.8 3 3.2 VCC [ V ] 3.4 3.6 3.8 www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. + 0 0.00 400 500 600 700 800 900 1000 Wavelength [nm] Fig.10 ALS Measurement Result VCC Dependency - 0.2 0.20 0 2.2 + 0.6 0.4 0.40 - Fig.11 PS Spectral Response 5/32 1100 -90 -60 -30 0 30 60 90 Angle [ deg ] Fig.12 PS Directional Characteristics 1 2011.06 - Rev.B BH1771GLC Technical Note 1.2 200 260 240 1 ICC @ Measurement [ uA ] 220 200 180 PS_DATAOUT Ratio 0.8 - 0.6 1pin - 0.4 160 140 120 100 80 + 60 0.2 + 150 100 50 40 20 0 -90 -60 -30 0 30 60 0 0 0.001 90 Angle [ deg ] 0.01 0.1 1 10 100 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8 VCC [ V ] 1000 Irradiance(mW/cm2] Fig.13 PS Directional Characteristics 2 Fig.15 VCC - ICC ( During PS measurement ) Fig.14 Irradiance – PS_DATAOUT 200 20 160 16 120 ICC @ POWER DOWN [ uA ] 24 ILEDC[mA] 12 80 8 40 4 0 0 0 1 2 3 4 5 0 6 1 3 4 5 Fig.16 VLEDC – ILEDC@ ILED is set 200mA by ILED register 0.1 6 -40 200 PS_DATAOUT [count] 140 130 120 110 -20 0 20 40 60 80 100 160 ILED=200mA LED : SIM-030ST Center to Center : 10mm between BH1771GLC and SIM-030ST 120 80 40 18％ Kodak GrayCard 0 50 100 Object Distance [mm] 150 200 120 80 SIM-030ST 40 PS_DATAOUT [count] ILED=200mA Reflector: 18%Kodak Graycard Center to Center : 10mm between BH1771GLC and Infrared LED A=5mm 160 A=20mm A=30mm 80 80 100 80 40 ILED=50mA 50 100 150 Object Distance [mm] Fig.21 Object Distance – PS_DATAOUT of different ILED ILED=200mA LED : SIM-030ST Reflector : 18%Kodak Graycard Center to Center : A between BH1771GLC and Infrared LED A=10mm 120 60 LED : SIM-030ST Reflector : 18%Kodak Graycard Center to Center : 10mm between BH1771GLC and SIM-030ST 120 0 Fig.19 PS sensor out Fig.20 Object Distance – PS_DATAOUT Temperature Dependency of different reflector 2 (Irradiance by Proximity object = 324μW/cm ) SIM-040ST 40 ILED=100mA 0 0 20 ILED=200mA Human hand 160 Ta [℃] 160 0 Fig.18 VCC – ICC@0 Lx ( POWER DOWN ) 90％ White paper 100 -40 -20 Ta [ ℃ ] Fig.17 VLEDC – ILEDC@ ILED is set 20mA by ILED register 150 PS_DATAOUT [count] 1 VLEDC [V] VLEDC [V] PS_DATAOUT [count] 2 PS_DATAOUT [count] ILEDC[mA] 10 240 A=50mm A=70mm 40 0 0 0 50 100 Object Distance [mm] 150 Fig.22 Object Distance – PS_DATAOUT of different Infrared LED www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 0 50 100 150 Object Distance [mm] Fig.23 Object Distance – PS_DATAOUT of different distance between BH1771GLC and SIM-030ST 6/32 2011.06 - Rev.B BH1771GLC Technical Note ・Fig.24-27 are PS_DATAOUT measurement results which depend on the position of the reflector. The reflector is a White paper of reflectivity 90% and this size is 50mm×50mm. The characteristic of 90%White paper is nearly similar to human hand(human palm). 1) The reflector moves to the parallel direction for the position of BH1771GLC and LED. Direction of reflector movement BH1771GLC LED : SIM-030ST 50mm BH1771GLC Reflector Reflector -A/2 +A/2 0 1pin A 50mm 80 A=10mm A=30mm A=50mm 120 100 PS_DATAOUT [count] PS_DATAOUT [count] 140 A=70mm 80 60 40 20 0 -100 -50 0 50 Height of reflector A=10mm A=30mm A=50mm 60 A=70mm 40 20 0 -100 100 Position of reflector [mm] -50 0 50 PCB Measurement conditions ・ILED=200mA ・LED : SIM-030ST ・Reflector : 90%White paper 50mm×50mm ・Center to Center : A (between BH1771GLC and SIM-030ST) ・Ambient irradiance = 0μW/cm2 100 Position of reflector [mm] Fig.25 Position of reflector – PS_DATAOUT Height of reflector is 100mm Fig.24 Position of reflector – PS_DATAOUT Height of reflector is 50mm 2) The reflector moves to the vertical direction for the position of BH1771GLC and LED. Direction of reflector movement LED : SIM-030ST LED : SIM-030ST 50mm Reflector A Reflector 0 - + 1pin 50mm Height of reflector BH1771GLC PCB BH1771GLC A=10mm 80 A=30mm 120 A=50mm 100 A=70mm 80 60 40 20 0 -100 -50 0 50 100 Position of reflector [mm] Fig.26 Position of reflector – PS_DATAOUT Height of reflector is 50mm www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. PS_DATAOUT [count] PS_DATAOUT [count] 140 A=10mm A=30mm A=50mm 60 A=70mm 40 20 0 -100 -50 0 50 Measurement conditions ・ILED=200mA ・LED : SIM-030ST ・Reflector : 90%White paper 50mm×50mm ・Center to Center : A (between BH1771GLC and SIM-030ST) ・Ambient irradiance = 0μW/cm2 100 Position of reflector [mm] Fig.27 Position of reflector – PS_DATAOUT Height of reflector is 100mm 7/32 2011.06 - Rev.B BH1771GLC Technical Note ●I2C bus communication 1) Slave address "0111000" 2) Main write format 1. Case of “Indicate register address” Slave Address 0111000 ST W 0 ACK Indicate register address 010XXXXX ACK SP 2. Case of "write to data register after indicating register address" Slave Address 0111000 ST Data specified at register address field W 0 ACK ACK ACK ・・・・・・ Indicate register address 010XXXXX ACK Data specified at register address field + N ACK SP BH1771GLC continues to write data with address increments until master issues stop condition. Write cycle is 40h - 41h - 42h - 43h - 44h - 45h - 46h – 52h ……… 5Dh – 5Eh - 40h ……… Ex ) If register address field is 45h, then BH1771GLC writes data like seeing in below. 45h - 46h -52h ……… 5Dh – 5Eh - 40h………It is continued until master issues stop condition. 3) Main read format 1. Case of read data after indicate register address and read data ( Master issues restart condition ) ST ST Slave Address 0111000 Slave Address 0111000 Data specified at register address field + 1 2. W 0 ACK R 1 ACK ACK ACK ・・・・・・ Indicate register address 010XXXXX ACK Data specified at register address field ACK Data specified at register address field + N NACK Data specified at register address field ACK Data specified at register address field + N NACK SP Case of read data after selecting register address ST Slave Address 0111000 Data specified at register address field + 1 R 1 ACK ・・・・・・ ACK ACK SP BH1771GLC outputs data from specified address field until master issues stop condition. Read cycle is 40h - 41h - 42h - 43h - 44h - 45h - 46h – 4Ah ……… 5Dh – 5Eh - 40h ……… Ex ) If register address field is 4Ch, then BH1771GLC outputs data like seeing in below. 4Ch - 4Dh -4Eh ……… 5Dh – 5Eh - 40h………It is continued until master issues stop condition. from slave to master from master to slave ※ ※ www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. BH1771GLC operates as I2C bus slave device. Please refer formality I2C bus specification of NXP semiconductors 8/32 2011.06 - Rev.B BH1771GLC Technical Note ●Block diagram and block explanation VDD LED IrLED VDD LED IrLED VCC VDD LED IrLED LED1 LED2 LED3 Proximity Sensor LED Pulse Gen. IrLED Drivers DC light rejection Amp Reflector GND_LED Ambient Light Linear ADC PS Control Logic Linear / Log converter PD_PS Data Registers INT interface INT POR Timing Controller OSC 16bit ADC ALS Control Logic PD_ALS I 2C Interface SDA SCL Ambient Light Sensor  I2C Interface GND GNDNC I2C bus interface. f/s mode and Hs mode is supported. 1.8V logic interface is supported.  POR Power on reset function.  OSC Internal oscillator.  Timing controller Internal management block for proximity sensor and ambient light sensor.  INT interface INT terminal control block. Details are on Page 14 - 16  DATA registers Register for strage of measurement results or commands. Details are on Page 17.  PS control logic This block controls proximity sensor analog block  LED Pulse Gen LED current generator. LED current value is configurable by ILED( 42h ) and ILED3( 43h ) register.  IrLED Drivers. IrLED driver block. Active LED terminal is set by ILED( 42h ) register.  PD_ALS Photo diode for ambient light sensor. Peak wavelength is approximately 550nm.  16bit ADC AD converter for ALS.  ALS control logic This block controls ambient light sensor analog block.  PD_PS Photo diode for proximity sensor. Peak wavelength is approximately 850nm.  DC light rejection Amp DC light is rejected in this block. And generated Infrared pulse is passed to linear ADC block.  Linear ADC 2 2 AD converter for proximity sensor. Detection range is very wide ( 1μW/cm - 100mW/cm ).  Linear/Log converter Linear to logarithm converter for proximity sensor. Output data is 8bit. PS irradiance calculation example is on Page 26. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 9/32 2011.06 - Rev.B BH1771GLC Technical Note ●Example of application circuit diagram If you do not use the INT pin, please connect to GND or opening (non connect). 1) In case of using 1IrLED (ex. SIM-030ST(Rohm)) 2.5 - 5.5V 2.3 – 3.6V IrLED (ex. 0.1μF) (ex. 10μF) 1.65 – 5.5V VCC 6 LED1 Proximity Sensor 3 LED2 LED3 2 LED Pulse Gen IrLED Drivers 1 DC light rejection Amp Data PS Control Logic INT INT interface 5 Linear / Log converter Linear ADC 1.65 – 3.6V PD_PS POR or OSC Timing Controller Baseband SCL I 2C Interface ALS Control Logic 16bit ADC Micro Controller Processor 8 SDA 9 PD_ALS Ambient Light Sensor 4 10 7 GND_LED GND GNDNC If you do not use the LED2 or LED3, please connect to VDD_LED or opening (non connect). 2) In case of using 3 IrLEDs (ex. SIM-030ST(Rohm)) IrLED IrLED 2.5 - 5.5V 2.3 – 3.6V IrLED (ex. 0.1μF) (ex. 10μF) 1.65 – 5.5V VCC 6 LED1 Proximity Sensor 3 LED2 LED3 2 LED Pulse Gen IrLED Drivers 1 DC light rejection Amp Data PS Control Logic INT INT interface 5 Linear / Log converter Linear ADC 1.65 - 3.6V PD_PS POR or OSC Timing Controller Baseband SCL I 2C Interface ALS Control Logic 16bit ADC Micro Controller 8 Processor SDA 9 PD_ALS Ambient Light Sensor 4 GND_LED www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 10 7 GND 10/32 GNDNC 2011.06 - Rev.B BH1771GLC Technical Note 3) In case of extending proximity sensor detection distance BH1771GLC can drive maximum 200mA(Typ) current. By adding simple external circuit, it is possible to increase IrLED current and to extend detection distance. In case of driving large current forIrLED, note that the current value must not be over the absolute maximum rating for IrLED. VDD_LED 4.5 - 5.5V 2.3 – 3.6V 1kOhm (ex. 0.1μF) (ex. 10μF) 1.65 – 5.5V VCC 6 PMOS LED1 (ex. SIM-030ST (Rohm)) Proximity Sensor 3 （ex. RTR030P02 (Rohm)） LED2 LED3 2 LED Pulse Gen IrLED Drivers 1 DC light rejection Amp IrLED Data PS Control Logic INT INT interface 5 Linear / Log converter Linear ADC 1.65 - 3.6V PD_PS POR or OSC Timing Controller Baseband SCL I 2C Interface ALS Control Logic 16bit ADC Micro Controller 8 Processor SDA 9 PD_ALS Ambient Light Sensor 4 GND_LED 10 7 GND GNDNC * In the case of the following setting for above circuit, LED current is proximity 500mA. VDD_LED=5V, R1=3.9Ohm www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 11/32 2011.06 - Rev.B BH1771GLC Technical Note ●Terminal description PIN No. 1 2 Terminal Name Equivalent Circuit Nch open drain LED3 terminal. LED current and emitting interval is defined by internal register. Register value is possible to configure by I2C bus. LED3 Nch open drain LED2 terminal. LED current and emitting interval is defined by internal register. Register value is 2 possible to configure by I C bus. LED2 3 LED1 4 GND_LED 5 INT 6 VCC 7 GND Function Nch open drain LED1 terminal. LED current and emitting interval is defined by internal register. Register value is possible to configure by I2C bus. GND terminal for LED driver Nch open drain output. Interrupt setting is defined by internal register. Register value is possible to 2 configure by I C bus. Power supply terminal GND terminal 2 I C bus Interface SCL terminal 8 SCL 2 I C bus Interface SDA terminal 9 SDA Non connect or pull down to GND VCC 10 GNDNC If you do not use the INT pin, please connect to GND or opening (non connect). If you do not use the LED2 or LED3, please connect to VDD_LED or opening (non connect). www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 12/32 2011.06 - Rev.B BH1771GLC Technical Note ●Proximity sensor measurement sequence The below figure shows proximity sensor measurement sequence. First PS measurement is triggered by I2C bus master writes measurement command to PS_CONTROL register ( 41h ). BH1771GLC has 3 LED-drivers and their combinations are set by ILED,ILED3 register ( 42h, 43h ). In the case of only LED2 is inactive, LED3 emit immediately after LED1 emittion. 1. Forced mode PS measurement is done only 1time and PS trigger bit ( 44h ) is overwritten from 'H' to ‘L’ after PS measurement complete. PS measurement is re-started by master writes PS trigger bit to 'H'. 2. Stand alone mode PS measurement is continuously done until master select the other mode. Measurement interval is defined at PS_MEAS_RATE register ( 45h ). start measurement LED1 LED2 LED3 start measurement LED1 LED2 LED3 PS meas rate tMPS twILED2 twILED twILED : twILED2 : tMPS : PS meas rate: LED current pulse duration, please refer P2 ( Electrical Characteristics ). Cumulative LED current pulse duration, please refer P2 ( Electrical Characteristics ). Proximity sensor measurement time, please refer P2 ( Electrical Characteristics ). Measurement result is generated in this term. In case of stand alone mode, It is defined at PS_MEAS_RATE register ( 45h ). In case of forced mode, it means the term until overwriting PS trigger bit to ‘H’. ●Ambient light sensor measurement sequence The below figure shows ambient light sensor measurement sequence. First ALS measurement is triggered by I2C bus master writing measurement command to ALS_CONTROL register ( 40h ). 1. Forced mode ALS measurement is done only 1time and ALS trigger bit( 44h ) is overwritten from 'H' to ‘L’ after ALS measurement is completed. ALS measurement is re-started by master writes ALS trigger bit to 'H'. 2. Stand alone mode ALS measurement is continuously done until master select the other mode. Measurement interval is defined at ALS_MEAS_RATE register ( 46h ). If ALS rate disable bit ( 46h ) is ‘H’, there is no interval between measurement. start measurement start measurement tMALS tMALS : ALS meas rate : ALS meas rate Ambient light sensor measurement time, please refer P2 ( Electrical Characteristics ). Measurement result is generated in this term. In case of stand alone mode, It is defined at ALS_MEAS_RATE register ( 46h ) In case of forced mode, it means the term until overwriting ALS trigger bit to ‘H’. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 13/32 2011.06 - Rev.B BH1771GLC Technical Note ●Interrupt function Interrupt function compares ALS or PS measurement result to preset interrupt threshold level. PS uses one threshold level or two threshold level ( in hysteresis mode ) and ALS uses two threshold level (upper and lower ). Interrupt status is monitored by INT pin or ALS_PS_STATUS register ( 4Eh ) and Interrupt function is able to be controlled by INTERRUPT register ( 52h ). Interrupt threshold is defined at ALS_TH_UP and ALS_TH_LOW and PS_TH_LED and PS_TH_L_LED registers ( 53h - 59h, 5Ch - 5Eh ). PS_TH_L_LED registers are effective when PS hysteresis bit ( 52h ) is ‘H’. Interrupt persistence function is defined at PERSISTENCE register ( 5Bh ). INT pin is Nch open drain terminal so this terminal should be pull-up to some kind of voltage source by an external resister. Maximum sink current rating of this terminal is 7mA. There are two output modes about interrupt function ( latched mode and unlatched mode ). In case of using ALS and PS interrupt functions at the same time, latch mode is recommended. INT terminal is high impedance when VCC is supplied. INT terminal becomes inactive by setting INTERRUPT register (52h)[1:0] to “00”. ( It is not worked during power down mode. Power down mode means ALS_CONTROL(40h)=’0’ and PS_CONTROL(41h) = ‘0’.) INT terminal keeps just previous state which power down command is sent. So to set INT terminal to high impedance is recommended. VCC current(approximately 25μA at VCC=2.5V) is consumed during INT terminal is ‘L’. There are two method to set INT terminal to high impedance. 1) Send software reset command. (Write ‘H’ to ALS_CONTROL(40h). Software reset is also worked during power down. All registers are initialized by software reset command.) 2) Write “000” to INTERRUPT register(52h). ex1) In case of using PS ‘H’ threshold （INTERRUPT register 52h : ‘0’） In case of unlatch mode if the measurement value exceed the PS interrupt threshold ‘H’ value, the interrupt becomes active. And if the measurement value goes below the threshold, the interrupt becomes inactive. In case of latch mode once the interrupt becomes active, it keeps the status until end of measurement after INTERRUPT register is read. In case of persistence function is set to active, if the interrupt is inactive, it keeps inactive status until the measurement value is beyond the threshold ‘H’ value continuously. If the interrupt is active, it keeps active status until the measurement value is below threshold ‘H’ value continuously or until end of measurement after INTERRUPT register is read. Master reads INTERRUPT register Latch mode Unlatch mode Unlatch mode persistence = 2 active inactive PS interrupt threshold ‘H’ level Sequential measurement result time www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 14/32 2011.06 - Rev.B BH1771GLC Technical Note ex2 ) In case of using PS ‘H/L’ threshold （( INTERRUPT register 52h : ‘1’) In case of unlatch mode if the measurement value exceed the PS interrupt threshold ‘H’ value, the interrupt becomes active. And if the measurement value is below the threshold “L” value, the interrupt becomes inactive. In case of latch mode once the interrupt becomes active, it keeps the status until end of measurement after INTERRUPT register is read. In case of persistence function is set to active, if the interrupt is inactive, it keeps inactive status until the measurement value is beyond the threshold ‘H’ value continuously. If the interrupt is active, it keeps active status until the measurement value is below threshold “L” value continuously or until end of measurement after INTERRUPT register is read. Master reads INTERRUPT register Latch mode Unlatch mode Unlatch mode persistence = 2 active inactive PS interrupt threshold ‘H’ level PS interrupt threshold ‘L’ level Sequential Sequential measurement measurement result result time www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 15/32 2011.06 - Rev.B BH1771GLC Technical Note ex3 ) Ambient light sensor interrupt function In case of unlatch mode if the measurement value is within the range set by ALS interrupt threshold ‘H’ and “L” value, the interrupt becomes inactive. And if the measurement value is out of the range set by threshold ‘H’ and ”L” value, the interrupt becomes active. In case of latch mode once the interrupt becomes active, it keeps the status until end of measurement after INTERRUPT register is read. In case that persistence function is set to active, if the interrupt is inactive, it keeps inactive status until the measurement value is continuously out of the range set by threshold ‘H’ and “L” value. If the interrupt is active, it keeps active status until the measurement value is continuously within the range set by threshold ‘H’ and ”L” value or until end of measurement after INTERRUPT register is read. Master reads INTERRUPT register Latch mode Unlatch mode Unlatch mode persistence = 2 active inactive ALS interrupt threshold ‘H’ level ALS interrupt threshold ‘L’ level Sequentialmeasurement measurementresult result Sequential time www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 16/32 2011.06 - Rev.B BH1771GLC Technical Note ●Command set Address 40h 41h Type RW RW Register name ALS_CONTROL PS_CONTROL Register function ALS operation mode control and SW reset PS operation mode control 42h RW I_LED 43h RW I_LED3 Selection of active LED and LED1, LED2 current setting LED3 current setting 44h RW ALS_PS_MEAS Forced mode trigger 45h RW PS_MEAS_RATE PS measurement rate 46h RW ALS_MEAS_RATE ALS measurement rate 4Ah R - Reserved 4Bh 4Ch 4Dh 4Eh 4Fh 50h 51h R R R R R R R MANUFACT_ID ALS_DATA_0 ALS_DATA_1 ALS_PS_STATUS PS_DATA_LED1 PS_DATA_LED2 PS_DATA_LED3 Manufacturer ID ALS data (Low Byte) ALS data (High Byte) Measurement data and interrupt status PS data from LED1 PS data from LED2 PS data from LED3 52h 53h 54h 55h 56h 57h 58h 59h 5Ah 5Bh 5Ch 5Dh 5Eh RW RW RW RW RW RW RW RW RW RW RW RW RW INTERRUPT PS_TH_LED1 PS_TH_LED2 PS_TH_LED3 ALS_TH_UP_0 ALS_TH_UP_1 ALS_TH_LOW_0 ALS_TH_LOW_1 ALS_SENSITIVITY PERSISTENCE PS_TH_L_LED1 PS_TH_L_LED2 PS_TH_L_LED3 Interrupt setting PS interrupt H threshold for LED1 PS interrupt H threshold for LED2 PS interrupt H threshold for LED3 ALS upper threshold low byte ALS upper threshold high byte ALS lower threshold low byte ALS lower threshold high byte ALS sensitivity setting INT pin INTERRUPT persistence setting PS interrupt L threshold for LED1 PS interrupt L threshold for LED2 PS interrupt L threshold for LED3 www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 17/32 2011.06 - Rev.B BH1771GLC Technical Note ○ ALS_CONTROL ( 40h ) 7 RES 6 5 4 3 2 1 0 RES RES RES ALS Resolution SW Reset ALS mode default value 00h Field Bit Type Description RES 7:4 RW ALS Resolution 3 RW SW reset 2 RW ALS mode 1:0 RW Write 0000 0 : H-Resolution mode, 1 lx step output 1 : M-Resolution mode, 4 lx step output 0 : initial reset is not started 1 : initial reset is started 00 : Standby mode 01 : Don’t use. 10 : Forced mode 11 : Stand alone mode ○ PS_CONTROL ( 41h ) 7 X 6 5 4 3 2 1 X X X X X PS mode default value 00h Field NA Bit 7:2 Type - PS mode 1:0 RW 0 Description Ignored 00 : Standby mode 01 : Don’t use. 10 : Forced mode 11 : Stand alone mode ○ I_LED ( 42h ) 7 6 PS active 5 4 LED2 current 3 2 1 LED1 current 0 default value 1Bh Field Bit Type PS active 7:6 RW LED2 current 5:3 RW LED1 current 2:0 RW www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. Description 00 : LED1 is active, LED2,3 are inactive 01 : LED1,2 are active, LED3 is inactive 10 : LED1,3 are active, LED2 is inactive 11 : All LEDs are active 000 : 5mA 001 : 10mA 010 : 20mA 011 : 50mA 100 : 100mA 101 : 150mA 11X : 200mA 18/32 2011.06 - Rev.B BH1771GLC Technical Note ○ I_LED3 ( 43h ) 7 6 5 4 3 2 1 X X X X X LED3 current 0 default value 03h Field NA LED3 current ○ ALS_PS_MEAS ( 44h ) 7 X Type - 2:0 RW Description Ignored 000 : 5mA 001 : 10mA 010 : 20mA 011 : 50mA 100 : 100mA 101 : 150mA 11X : 200mA 6 5 4 3 2 1 X X X X X ALS PS trigger trigger default value 00h Field NA *2 Bit 7:3 Bit 7:2 Type - ALS trigger 1 RW PS trigger 0 RW 0 Description Ignored 0 : Ignored 1 : Start ALS measurement at force mode*2 0 : Ignored 1 : Start PS measurement at force mode *2 Even if trigger is set during measurement, the measurement doesn’t start. The measurement will start, in case that It is set to forced mode by ALS_CONTROL register (40h) or PS_CONTROL register (41h) and is not during measurement. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 19/32 2011.06 - Rev.B BH1771GLC Technical Note ○ PS_MEAS_RATE ( 45h ) 7 6 X X 5 4 3 2 1 X X PS meas rate 0 default value 05h Field NA Bit 7:4 Type - PS meas rate 3:0 RW ○ ALS_MEAS_RATE ( 46h ) 7 6 ALS rate disable 5 4 X Description Ignored 0000 : 10ms 0001 : 20ms 0010 : 30ms 0011 : 50ms 0100 : 70ms 0101 : 100ms 0110 : 200ms 0111 : 500ms 1000 : 1000ms 1001 : 2000ms 101X : 2000ms 11XX : 2000ms 3 X X 2 X 1 0 ALS meas rate default value 02h Field Bit Type 7 RW 6:3 - ALS rate disable NA ALS meas rate 2:0 RW Description 0 : ALS meas rate( 46h ) is active 1 : ALS meas rate( 46h ) is inactive Ignored 000 : 100ms 001 : 200ms 010 : 500ms 011 : 1000ms 1XX : 2000ms ○ ( 4Ah ) 7 6 5 4 3 2 1 X X X X X X X Field NA www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. Bit 7:0 Type R 0 X default value 93h Description Reserved 20/32 2011.06 - Rev.B BH1771GLC Technical Note ○ MANUFACT_ID ( 4Bh ) 7 6 Manufacturer ID 5 4 3 2 1 0 default value 01h Field Manufacturer ID ○ ALS_DATA ( 4Ch, 4Dh ) 7 6 Bit 7:0 5 Type R 4 Description 00000001 3 2 1 0 ALS data default value 00h Register ALS data LSBs ALS data MSBs ○ ALS_PS_STATUS ( 4Eh ) 7 6 ALS ALS data INT status status Address 4Ch 4Dh 4 LED3 data status 3 LED2 INT status Bit Type Description ALS INT status 7 R ALS data status 6 R LED3 INT status 5 R LED3 data status 4 R LED2 INT status 3 R LED2 data status 2 R LED1 INT status 1 R LED1 data status 0 R Field 5 LED3 INT status Bit 7:0 7:0 Type R R 2 LED2 data status Description ALS data Low byte ALS data High byte 1 0 LED1 LED1 data INT status status default value 00h 0 : ALS interrupt signal inactive 1 : ALS interrupt signal active 0 : ALS old data (data is already read) 1 : ALS new data (data is renewed after previous reading) 0 : LED3 interrupt signal inactive 1 : LED3 interrupt signal active 0 : LED3 old data (data is already read) 1 : LED3 new data (data is renewed after previous reading) 0 : LED2 interrupt signal inactive 1 : LED2 interrupt signal active 0 : LED2 old data (data is already read) 1 : LED2 new data (data is renewed after previous reading) 0 : LED1 interrupt signal inactive 1 : LED1 interrupt signal active 0 : LED1 old data (data is already read) 1 : LED1 new data (data is renewed after previous reading) ALS interrupt signal inactive means that ALS measurement result is within threshold level set by ALS_TH register(56h, 57h, 58h, 59h). ALS interrupt signal active means measurement result is out of threshold level set by ALS_TH register. PS interrupt signal active means each PS measurement result exceeds threshold level defined by PS_TH_LED register(53h, 54h, 55h). PS interrupt signal inactive means each PS measurement result does not exceed threshold level set by PS_TH_LED register. When PS interrupt hysteresis( INTERRUPT register 52h) is ‘H’, if once interrupt signal becomes active, it is kept until measurement result becomes less than PS_TH_L_LED( 5Ch 5Dh 5Eh) register value. Regarding ALS and LED1, it is possible to set persistence (5Bh). www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 21/32 2011.06 - Rev.B BH1771GLC Technical Note ○ PS_DATA_LED ( 4Fh, 50h, 51h) 7 6 5 4 3 2 1 0 LED data default value 00h Register LED1 data LED2 data LED3 data ○ INTERRUPT ( 52h ) 7 X Address 4Fh 50h 51h 6 5 Interrupt source Bit 7:0 7:0 7:0 4 PS Interrupt hysteresis Type R R R Description PS measurement data for each LED 3 2 1 Output mode Interrupt polarity Interrupt mode 0 default value 08h Field NA Bit 7 Type - 6:5 R PS Interrupt hysteresis 4 RW Output mode 3 RW Interrupt polarity 2 RW 1:0 RW Interrupt source Interrupt mode Description Ignored 00 : First interrupt triggered by ALS 01 : First interrupt triggered by LED1 10 : First interrupt triggered by LED2 11 : First interrupt triggered by LED3 0 : Use PS_TH_LED only. 1 : Use PS_TH_LED and PS_TH_L_LED for hysteresis 0 : INT pin is latched until INTERRUPT register is read. 1 : INT pin is updated after each measurement. 0 : INT pin is logic “L” when interrupt signal is active 1 : INT pin is logic “L” when interrupt signal is inactive 00 : INT pin is inactive. 01 : Triggered by only PS measurement 10 : Triggered by only ALS measurement 11 : Triggered by PS and ALS measurement ○ PS_TH_LED ( 53h, 54h, 55h) 7 6 5 4 3 2 1 0 LED threshold default value FFh Register LED1 threshold LED2 threshold LED3 threshold www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. Address 53h 54h 55h Bit 7:0 7:0 7:0 22/32 Type RW RW RW Description PS H threshold for each LED 2011.06 - Rev.B BH1771GLC Technical Note ○ ALS_TH_UP ( 56h, 57h ) 7 6 5 4 3 2 1 0 ALS upper threshold data default value FFh Register Address Bit Type ALS TH upper LSBs 56h 7:0 RW ALS TH upper MSBs 57h 7:0 RW ○ ALS_TH_LOW ( 58h, 59h ) 7 6 5 4 3 2 Description ALS interrupt upper threshold (Low byte) ALS interrupt upper threshold (High byte) 1 0 ALS lower threshold data default value 00h Register Address Bit Type ALS TH lower LSBs 58h 7:0 RW ALS TH lower MSBs 59h 7:0 RW ○ ALS_SENSITIVITY ( 5Ah ) 7 6 5 4 3 2 Description ALS interrupt lower threshold (Low byte) ALS interrupt lower threshold (High byte) 1 0 ALS sensitivity data default value 35h Register ALS sensitivity data ○ PERSISTENCE ( 5Bh ) 7 6 ALS persistence 5 Bit 7:0 4 Type RW Description ALS sensitivity adjustment register（refer to P27） 3 2 1 PS LED1 persistence 0 default value 11h Field ALS persistence PS LED1 persistence ○ PS_TH_L_LED ( 5Ch, 5Dh, 5Eh) 7 6 LED L threshold 5 Bit 7:4 3:0 4 Type RW RW Description Persistence for ALS interrupt. Persistence for PS LED1 interrupt. 3 2 1 0 default value 00h Register LED1 L threshold LED2 L threshold LED3 L threshold www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. Address 5Ch 5Dh 5Eh Bit 7:0 7:0 7:0 23/32 Type RW RW RW Description PS L threshold for each LED 2011.06 - Rev.B BH1771GLC Technical Note ●Current consumption BH1771GLC can operate ALS and PS individually. Average current consumption is depend on each statuses and measurement duration (set by 45h, 46h register). Major elements which decide VCC current consumption are like following table. Parameter ALS part’s current PS part’s current PS current during driving LED ALS/PS common ciruit current 1) Symbol Typ. Units IccALS 140 μA Except for ALS/PS common circuit current. Except for ALS/PS common circuit current. Current flow for 1.4ms (in case of using one LED) Current flow for 1.8ms (in case of using two LEDs) Current flow for 2.2ms (in case of using three LEDs) IccPS 250 μA Icc3 6.5 mA Icccmn 60 μA Comment Current consumption in case of operating only ALS VCC current consumption can calculate according to following formula. ICC(only ALS) = IccALS * ( 100ms / ALS meas rate ) +Icccmn For example in case measurement rate is 500ms, the value is as following. e. g. ) ICC(only ALS) = 140μA (100ms / 500ms) + 60μA = 88μA 2) Current consumption in case of operating only PS VCC current consumption can calculate according to following formula. ICC(only PS) = IccPS * ( 1.4ms / PS meas rate ) +Icccmn + Icc3 * ( 200μs / PS meas rate* number of LEDs ) VDD_LED current consumption can calculate according to following formula. IVDD_LED = (ILED1 + ILED2 + ILED3) * (200μs / PS meas rate) For example in case it drives 50mA for only LED1 and measurement rate is 100ms, the value is as following. e. g. ) ICC(only PS) = 250μA * ( 1.4ms / 100ms ) + 60μA + 6.5mA * ( 200μs / 100ms * 1 ) = 76.5μA IVDD_LED = (50mA + 0 + 0) * (200μs / 100ms) = 100μA For example in case it drive 200mA for LED1,2 and 3 and measurement rare is 10ms, the value is as following. e. g. ) ICC(only PS) = 250μA * ( 2.2ms / 10ms ) + 60μA + 6.5mA * ( 200μs / 10ms * 3 ) = 505μA IVDD_LED = ( 200mA + 200mA + 200mA ) * (200μs / 10ms) = 12mA 3) Current consumption in case of operating ALS and PS at the same time. VCC current consumption can calculate according to following formula. ICC( ALS+PS) = Icc(only ALS) + Icc(only PS) - Icccmn For example in case ALS measurement rate is 500ms and PS measurement rate is 100ms and it drives 50mA for only LED1, the value is as following. e.g. ) ICC(ALS+PS) = 88μA + 76.5μA - 60μA = 104.5μA VDD_LED current consumption can calculate same as the case of operating only PS. 4) 2 I C bus High speed mode BH1771GLC support I2C bus Hs mode. VCC current consumption increases approximately 80μA during Hs- mode. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 24/32 2011.06 - Rev.B BH1771GLC Technical Note A 8-bit Master code 00001xxx t1 S tH SDAH SCLH 1 7 6 2 to 5 8 9 F/S mode 7-bit SLA Sr A R/W n x (8-bit DATA + A/A) Sr P SDAH SCLH 1 2 to 5 6 7 8 9 1 2 to 5 Hs-mode 6 7 8 9 tFS If P then F/S mode If Sr (dotted lines) then Hs mode tH = MCS current source pull-up = Rp resistor pull-up 5) Current consumption increases approximately 80uA 80μA in this term In case of waiting trigger at forced mode ALS/PScommon cucuit current （Icccmn） is flow. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 25/32 2011.06 - Rev.B BH1771GLC Technical Note ●ALS Measurement mode explanation Measurement Mode H-Resolution mode M-Resolution mode Measurement Time typ. 100ms. typ.16ms. Resolution 1 Lx 4 Lx We recommend to use H-Resolution Mode. Measurement time ( integration time ) of H-Resolution mode is so long that some kind of noise( including in 50Hz / 60Hz noise ) is rejected. And H-Resolution mode is 1 l x resolution so that it is suitable for darkness. ●Regarding ALS measurement result ALS measurement result is registered as following format ALS DATA LSB ( 4Ch ) 7 6 5 4 3 2 1 0 26 25 24 23 22 21 20 ALS DATA MSB ( 4Dh ) 7 6 215 214 5 213 4 212 3 211 2 210 1 29 0 28 27 ALS Lux calculation example ALS DATA LSB = ” 1001_0000 ” ALS DATA MSB = ” 1000_0011 ” ( 215 + 29 + 28 + 27 + 24 ) ≒ 33680 [ lx ] ●Regarding PS measurement result PS measurement result is converted to logarithm 8bit data and is registered as following format PS_DATA_LED1 ( 4Fh ), PS_DATA_LED2 ( 50h ), PS_DATA_LED3 ( 51h ) 7 6 5 4 3 2 1 7 6 5 4 3 2 2 2 2 2 2 2 21 The data seeing above registers are possible to change the irradiance. Approximation formula is seeing in below. Irradiance : 10 ^ (PS_DATA_LED * 0.0197) [μW/cm^2] 0 20 PS irradiance calculation example PS_DATA_LED1 = ” 1000_0101 ” 10 ^ ( (27 + 22 + 20 ) x 0.0197) = 10^(133 x0.0197) ≒ 417 [μW/cm^2 ] www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 26/32 2011.06 - Rev.B BH1771GLC Technical Note ●ALS sensitivity adjustment function BH1771GLC is possible to change ALS sensitivity. And it is possible to cancel the optical window influence ( difference with / without optical window ) by using this function. Adjustment is done by changing measurement time. For example, when transmission rate of optical window is 50% (measurement result becomes 0.5 times if optical window is set), influence of optical window is ignored by changing sensor sensitivity from default to 2 times. Sensitivity can be adjusted by ALS_SENSITIVITY(5Ah). For example, sensitivity 2 times when the value of the register is 2 times, and the measurement time 2 times, too. The range of adjusting ALS_SENSITIVITY is below. Adjustable range of ALS_SENSITIVITY binary decimal Min. 0001_1000 (sensitivity: default * 0.45 ) 24 (sensitivity: default * 0.45 ) Typ. 0011_0101 default 53 default Max. 1111_1110 (sensitivity: default * 4.79 ) 254 (sensitivity: default * 4.79 ) It is possible to detect 0.21lx by using this function at H-resolution mode. The below formula is to calculate illuminant per 1 count. Illuminant per 1 count ( lx / count ) = 1 * 53 / X 53 : Default value of ALS_SENSITIVITY register (decimal) X : ALS_SENSITIVITY register value (decimal) Illuminant per 1 count is as following within adjustable range of ALS_SENSITIVITY. ALS_SENSITIVITY register value 0001_1000 0011_0101 Illuminant per 1count(lx / count) 2.21 1.00 1111_1110 0.21 Please input the opecode at Power Down state to change ALS_SENSITIVITY register. There is a possibility of malfunction when the opecode to change ALS_SENSITIVITY register is input while the illuminant measurement is on-going In stand alone mode, if ALS measurement time exceeds the value defined ALS_MEAS_RATE register, ALS_MEAS_RATE register value is ignored. Next measurement is started immediately after one measurement completion. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 27/32 2011.06 - Rev.B BH1771GLC Technical Note ●Recommended land pattern unit : mm ●Optical window design above the device Sensing area; (0.55mm x 0.55mm) 1.4 Min. 0.55 Min. 0.55 Recommended light receiving area; Please design the optical window so that light can cover at least this area. Min. 0.55 Min. 0.55 unit : mm 1.4 www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 28/32 2011.06 - Rev.B BH1771GLC ● Technical Note The method of distinguishing 1pin There is the following methods of distinguishing 1pin. ① Distinguishing by Pad design of top side. There are 5 pads in the one side of a top side. There is a space between 2 pads and 3 pads. ② Distinguishing by Die pattern. 1Pin 2 pads A ① B 3 pads ②Die pattern Top View ③ Distinguishing by Pad design of bottom side. 1Pin Bottom View Pad of 1pin cuts the corner. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 29/32 2011.06 - Rev.B BH1771GLC Technical Note ●Power on reset function BH1771GLC has power on reset function. By operating this function, all of registers are reset when the power is supplied. Please note followings and design the application. ① Power on time : t1 BH1771GLC becomes operational after 2ms since VCC voltage crosses 1.9V from being less than 0.4V. ② Power off time : t2 Before the power is supplied, VCC voltage should be less than 0.4V at least for 1ms. 1.9V VCC 0.4V t1 t2 t1 BH1771GLC Don’t care active Don’t care active *”active state” means that BH1771GLC is correctly operational. INT terminal is high impedance when VCC is supplied. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 30/32 2011.06 - Rev.B BH1771GLC Technical Note ●Cautions on use 1) Absolute Maximum Ratings An excess in the absolute maximum ratings, such as supply voltage ( Vccmax, VSDAmax, VSCLmax, VINTmax, VGNDNCmax, VLEDmax ), temperature range of operating conditions ( Topr ), etc., can break down devices, thus making impossible to identify breaking mode such as a short circuit or an open circuit. If any special mode exceeding the absolute maximum ratings is assumed, consideration should be given to take physical safety measures including the use of fuses, etc. 2) GND voltage Make setting of the potential of the GND terminal and GND_LED terminal so that they will be maintained at the minimum in any operating state. Furthermore, check to be sure no terminals are at a potential lower than the GND voltage including an actual electric transient. 3) Short circuit between terminals and erroneous mounting In order to mount ICs on a set PCB, pay thorough attention to the direction and offset of the ICs. Erroneous mounting can break down the ICs. Furthermore, if a short circuit occurs due to foreign matters entering between terminals or between the terminal and the power supply or the GND terminal, the ICs can break down. 4) Operation in strong electromagnetic field Be noted that using ICs in the strong electromagnetic field can malfunction them. 5) Inspection with set PCB On the inspection with the set PCB, if a capacitor is connected to a low-impedance IC terminal, the IC can suffer stress. Therefore, be sure to discharge from the set PCB by each process. Furthermore, in order to mount or dismount the set PCB to/from the jig for the inspection process, be sure to turn OFF the power supply and then mount the set PCB to the jig. After the completion of the inspection, be sure to turn OFF the power supply and then dismount it from the jig. In addition, for protection against static electricity, establish a ground for the assembly process and pay thorough attention to the transportation and the storage of the set PCB. 6) Input terminals In terms of the construction of IC, parasitic elements are inevitably formed in relation to potential. The operation of the parasitic element can cause interference with circuit operation, thus resulting in a malfunction and then breakdown of the input terminal. Therefore, pay thorough attention not to handle the input terminals; such as to apply to the input terminals a voltage lower than the GND respectively, so that any parasitic element will operate. In addition, apply to the input terminals a voltage within the guaranteed value of electrical characteristics. 7) Thermal design Perform thermal design in which there are adequate margins by taking into account the power dissipation ( Pd ) in actual states of use. 8) Treatment of package Dusts or scratch on the photo detector may affect the optical characteristics. Please handle it with care. 9) RUSH current When power is first supplied to the CMOS IC, it is possible that the internal logic may be unstable and rush current may flow instantaneously. Therefore, give special consideration to power coupling capacitance, power wiring, width of GND wiring, and routing of connections. www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 31/32 2011.06 - Rev.B BH1771GLC Ordering part number B H 1 Part No. 7 7 1 G Part No. L C - Package GLC: WLGA010V28 E 2 Packaging and forming specification E2:Embossed tape and reel WLGA010V28 2.8±0.1 2.65±0.1(MOLD) Top View 0.9± 0.1 2.65±0.1(MOLD) 2.8± 0.1 8 1 4 9 6 Tape Embossed carrier tape (with dry pack) Quantity 3000pcs Direction of feed E2 The direction is the 1pin of product is at the upper left when you hold ( reel on the left hand and you pull out the tape on the right hand ) S 0.08 S Bottom View 0.5 0.4 1.0 9 0.35 0.7 0.7 0.7 0.35 0.2 0.4 0.4 0.4 2.0 2.8± 0.1 1 6 0.5 0.4 2.8±0.1 4 0.2 ● Technical Note 1.0 0.4 www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. 1pin (Unit : mm) Reel 32/32 Direction of feed ∗ Order quantity needs to be multiple of the minimum quantity. 2011.06 - Rev.B Notice Notes No copying or reproduction of this document, in part or in whole, is permitted without the consent of ROHM Co.,Ltd. The content specified herein is subject to change for improvement without notice. The content specified herein is for the purpose of introducing ROHM's products (hereinafter "Products"). If you wish to use any such Product, please be sure to refer to the specifications, which can be obtained from ROHM upon request. Examples of application circuits, circuit constants and any other information contained herein illustrate the standard usage and operations of the Products. The peripheral conditions must be taken into account when designing circuits for mass production. Great care was taken in ensuring the accuracy of the information specified in this document. However, should you incur any damage arising from any inaccuracy or misprint of such information, ROHM shall bear no responsibility for such damage. The technical information specified herein is intended only to show the typical functions of and examples of application circuits for the Products. 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If a Product is intended to be used for any such special purpose, please contact a ROHM sales representative before purchasing. If you intend to export or ship overseas any Product or technology specified herein that may be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to obtain a license or permit under the Law. Thank you for your accessing to ROHM product informations. More detail product informations and catalogs are available, please contact us. ROHM Customer Support System http://www.rohm.com/contact/ www.rohm.com © 2011 ROHM Co., Ltd. All rights reserved. R1120A