The TSL2550 is a digital light sensor with a two-wire, SMBus serial interface. It combines two photodiodes and a companying analog-to-digital converter (ADC) on a single CMOS integrated circuit to provide light measurements over an effective 12-bit dynamic range.

The TSL2550 is designed for use with broad wavelength light sources. One of the photodiodes (Channel 0) is sensitive to visible and infrared light, while the second photodiode (Channel 1) is sensitive primarily to infrared light. An integrating ADC converts the photodiode currents to Channel 0 and Channel 1 digital outputs. Channel 1 digital output is used to compensate for the effect of the infrared component of ambient light on Channel 0 digital output. The ADC digital outputs of the two channels are used to obtain a value that approximates the human eye response in the commonly used unit of Lux.

This device is intended primarily for use in applications in which measurement of ambient light is used to control display backlighting such as laptop computers, PDAs, camcorders, and GPS systems. Other applications include contrast control in LED signs and displays, camera exposure control, lighting controls, etc. The integrating conversion technique used by the TSL2550 effectively eliminates the effect of flicker from AC-powered lamps, increasing the stability of the measurement.

· Converts Light Intensity to Digital Signal

· Infrared Compensation to Approximate

· Human Eye Response

· Companding A/D for Wide Dynamic Rejects 50 Hz/60 Hz Lighting Ripple

· Two-Wire SMBus Serial Interface

· Single Supply Operation (2.7 V to 5.5 Low Active Power (1 mW typ)

· Power Down Mode

· Low-Profile Surface-Mount Package

Use the links below to view all of the TAOS light-sensing products as well as their data sheets:

· The TAOS family of intelligent opto sensors includes:

o Light-to-Voltage Sensors
Low-cost, photodiode with integrated transimpedance amplifier delivering linear analog voltage output

o Light-to-Frequency Sensors
Large input dynamic range measuring light intensity with pulse train or square wave digital output

o Linear Sensor Arrays
Spatial relationship optical sensor for imaging, encoding or edge detection with high linearity and uniformity

o Light to Digital Sensors
Digital light level measurement in units of lux approximating the human eye response

o Color Sensors
RGB filtered sensors for color discrimination, determination, and measurement.

About Texas Advanced Optoelectronic Solutions (TAOS), Inc. : Shaping the Future of Light Sensing Solutions

Texas Advanced Optoelectronic Solutions, Incorporated (TAOS) is based in Plano, Texas (a suburb of Dallas). Established in 1998, the company mission is "To Redefine Optoelectronic Solutions to Provide Cost and Performance Advantages by Creating and Managing Technology."

Historically, applications that require the sensing of light stimulus to execute a function have been implemented by either a photodiode or phototransistor – neither of which support the emerging needs for higher performance optical sensor-based applications.

Utilizing state-of-the-art technology, our semiconductor devices combine precision mixed-signal functionality with photo-detectors on the same integrated circuit to produce products with performance and cost advantages over conventional solutions. TAOS's intelligent opto sensors simplify the measurement and analog-to-digital conversion of light, and are designed to reduce the need for signal conditioning or pre-processing circuitry in light-centric systems. Our light sensing solutions improve system performance and reduce design-cycle time giving designers the flexibility and performance they require at an attractive system cost.