Innovations Embedded Sensors Ambient Light Sensor ICs for automatic light control processing < LCD ROHM MarketingUSA TV / Displays < LCD-equipped Portable Devices Selection Guide Ambient Light Sensor ICs from ROHM Semiconductor ROHM ambient light sensor (ALS) ICs Mobile Phones are designed to control the brightness of Digital Cameras LED-backlighted LCD displays based on Video Players ambient light availability and brightness PDAs Notebook PCs Car Navigation systems LCD TVs LCD Monitors /Displays for optimum display visibility and energy efficiency. The compact ROHM ALS ICs are the ideal choice for LCD-equipped portable devices as well as LCD monitors and ROHM’s advanced ambient light sensor ICs are offered in ultra-small WSOF5 and WSOF6 packages high-definition (HDTV) backlighting control. Improved Visibility with Lower Power Consumption Adjusting the backlight intensity to compensate for variations in ambient light level can save 50% or more of the total between charges (“talk time”) and/or the light sources. ROHM ALS ICs feature ability to extend the device’s feature set. industry-leading performance that To provide superior performance, combines stable operation regardless power required to operate some portable backlight brightness control must be of the light source (from incandescent electronic devices. This translates into done in a uniform way over a wide to sunlight) with superior light sensing dramatic improvement in operating time range of ambient light conditions and accuracy. Stable operation regardless of light source ROHM ambient light sensor ICs deliver stable output under a variety of light sources (e.g. incandescent, fluorescent, sunlight). 1.888.775.ROHM Superior light sensing accuracy Unique laser trimming technology ensures high sensitivity accuracy –– ±15% –– more than twice as precise as conventional ICs, which can range from ±30% to ±55%. www.rohmsemiconductor.com CNA09016_sg Ambient Light Sensor ICs from ROHM Semiconductor ROHM ambient light sensor ICs are in a typical application, an external ROHM Semiconductor ambient light available in both analog and digital resistor converts the output current to sensors all operate over a temperature configurations. The key features of a voltage for input to an MCU which range of -40 to 85°C to ensure stable each type are highlighted in the next in turn controls the LED driver. Direct operation under extreme conditions. two pages of this selection guide. connection to an LED driver is also Analog and digtial ALS ICs are each ROHM analog ALS ICs have an output possible (see page 6 for details). offered in compact, surface-mount current proportional to light (current ROHM Digital ALS ICs output a 16-bit packages. Package choices include the sourcing) with a measurement range (0 to ~65,535 lx) digital signal over a utra-small WSOF5 (1.6x1.6x0.55 mm) 2 direct I C bus interface to the MCU. of 0 to 100,000+ lux. As shown below, or WSOF6 (3.0x1.6x0.7 mm). Analog Output Ambient Light Sensor ICs Bright Control t%$ t18. t*2C Microcontroller or Baseband Processor LED Driver ALS (BH16xx) ADC WSOF5 *OUT Driver S/W Light GC1 GC2 Gain Control Digital Output Ambient Light Sensor ICs LED Driver Microcontroller or Baseband Processor *2C *' Driver S/W 1.888.775.ROHM SCL ALS (BH17xx) WSOF6 SDA SCL SDA Light www.rohmsemiconductor.com CNA09016_sg Ambient Light Sensor ICs from ROHM Semiconductor Analog Output Type The BH16xx Series of analog ambient light sensors combine a to make the appropriate trade-off between backlight intensity number of innovations to provide exceptional performance over and power consumption. A logic-enabled shutdown function is a wide range of applications. ROHM’s proprietary trimming also provided to further enhance power efficiency. In addition, process and use of multiple photodiodes with different junction the current souce output supports full rail-to-rail voltage depths provides a stable output with little variation between operation, further improving control sensitivity to variations in various light sources. Three levels of gain enable the designer light intensity. Uniform Sensitivity Built-in Shutdown Function 1: Connect to VCC 0: Connect to GND Three-Step Output Gain Wide Output Range 1.888.775.ROHM www.rohmsemiconductor.com CNA09016_sg Ambient Light Sensor ICs from ROHM Semiconductor Digital (16-bit Serial) Output Type The BH17xx series of digital ambient light sensors ICs employ Two measurement resolution levels are provided, allowing the same proprietary trimming and multiple photodiodes to design trade-offs between sampling time and performance. assure uniform light sensitivity. The device’s 16-bit analog-to- For example, with high-resolution sampling, optical noise like digital converter produces 1 lux resolution over a range of 0 fluorescent lamp flicker can be filtered. Low resolution reduces 2 to 65,000 lx. The I C output is designed for direct connection the sampling time for applications like GPS systems where the to the system’s microcontroller or baseband processor. light level changes are dynamic. 50Hz/60Hz Optical Noise Elimination Uniform Sensitivity Optical Window Sensitivity Control Wide I2C Input Voltage +UHVR +UHVROXWLRQPRGH UHV UH HHVV OXWLRQ XWLR XWL XW WLR WWL L PRGH PRG PPR RRG G 1.888.775.ROHM ROHM’s I2C bus is compatible with operating voltages between 1.65V and Vcc (3.6V, max) enabling operation in systems with multiple power supplies. www.rohmsemiconductor.com CNA09016_sg Ambient Light Sensor ICs Design Tools Ambient Light Sensor Evaluation Kits Evaluation kits for ROHM analog and digital ALS ICs are coming soon. Each kit Sensitivity setting IC communication display consists of a USB-connected PC board and a CD-ROM with software provided Measurement illuminance display to simulate and measure ambient light response. For more information, go to: www.rohmsemiconductor.com/als.html Optical Window Design Support Applying an ALS requires both optical and semiconductor expertise to assure mounting of the IC with a suitable optical window for light reception. ROHM’s “Optical Window Design Manual” ROHM’s ambient light sensor Optical Window Design Manual provides design guidance to facilitate the ROHM’s ambient light sensor IC Optical Simulation Report design process. For more information, go to: www.rohmsemiconductor.com/als.html Simplified Ambient light Control The ROHM BD16xx Series ALS ICs are designed to interface directly to ROHM LED drivers (BD60xxGU) to automatically 2 IC I/F SCL SDA control white LED backlights in portable devices without any requirement for light control software. An MCU is not Microcontroller or Baseband Processor CPU Load Reduced ROHM LED Driver IC with Automatic Light Control Function (BD6086GU) (BD6095GUL) Ambient light output IOUT Ambient light sensor IC (BH16xx series) Performs light output processing Light necessary but may still be used to GC1 GC2 provide control input to the ALS gain and Gain Switching Shutdown shutdown functions, as shown. For more information, go to: www.rohmsemiconductor.com/als.html 1.888.775.ROHM www.rohmsemiconductor.com CNA09016_sg Ambient Light Sensor ICs Part Selection Guide Analog Current Output Type Ambient Light Sensor ICs Part Number Output Type Power Supply Voltage (V) Sensitivity Variation (%) Number of Output Sensitivity Switching Levels Illuminance Measurement Range (lx) Operating Temperature Range (°C) Package BH1603FVC Current (Source) 2.4 to 5.5 ±15 3 steps 0 to 100,000 -40 to +85 WSOF6 BH1620FVC Current (Source) 2.4 to 5.5 ±15 3 steps 0 to 100,000 -40 to +85 WSOF5 BH1603FVC BH1620FVC Digital 16-bit Serial Output Type Ambient Light Sensor ICs Part Number Output Type Power Supply Voltage (V) Sensitivity Variation (%) I/O Voltage Illuminance Measurement Range (lx) Operating Temperature Range (°C) Package BH1715FVC I2C I/F 2.6 to 3.6 ±15 1.65 to Vcc 0 to 65,000 -40 to +85 WSOF6 2 BH1721FVC I C I/F 2.4 to 3.6 ±15 1.65 to Vcc 0 to 65,000 -40 to +85 WSOF5 BH1750FVI I2C I/F 2.4 to 3.6 ±20 1.65 to Vcc 0 to 65,000 -40 to +85 WSOF6I BH1715FVC BH1721FVC BH1750FVI Key Analog output Serial output High-accuracy detection Supply voltage 2.4V~3.6V/5.5V Output current source type Compatible with 1.8V systems Transparent package type OμA standby current Compact surface-mount package Supports I2C bus I/F Gain switching Wide dynamic range 1.888.775.ROHM www.rohmsemiconductor.com Built-in 16-bit AD converter Spectral sensitivity close to the human eye Wide operating temperature range: -40C to +85C CNA09016_sg 10145 Pacific Heights Blvd., Suite 1000 San Diego, CA 92121 www.rohmsemiconductor.com | 1.888.775.ROHM NOTE: For the most current product information, contact a ROHM sales representative in your area. ROHM assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representations that the circuits are free from patent infringement. Specifications subject to change without notice for the purpose of improvement. The products listed in this catalog are designed to be used with ordinary electronic equipment or devices (such as audio visual equipment, office-automation equipment, communications devices, electrical appliances and electronic toys). Should you intend to use these products with equipment or devices which require an extremely high level of reliability and the malfunction of which would directly endanger human life (such as medical instruments, transportation equipment, aerospace machinery, nuclear-reactor controllers, fuel controllers and other safety devices), please be sure to consult with our sales representative in advance. © 2009 ROHM Semiconductor USA, LLC. Although every effort has been made to ensure accuracy, ROHM accepts no responsibility for errors or omissions. Specifications and product availability may be revised without notice. No part of this document represents an offer or contract. Industry part numbers, where specified, are given as an approximate comparative guide to circuit function only. Consult ROHM prior to use of components in safety, health or life-critical systems. All trademarks acknowledged. 1.888.775.ROHM www.rohmsemiconductor.com CNA09016_sg