Datasheet:TSL2550 AMBIENT LIGHT SENSOR WITH SMBus INTERFACE

The TSL2550 is a digital-output light sensor with a two-wire, SMBus serial interface. It combines two photodiodes and a companding analog-todigital converter (ADC) on a single CMOS integrated circuit to provide light measurements over an effective 12-bit dynamic range with a response similar to that of the human eye. 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.