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NEW PRODUCT NEWS—edited by Harv Weiner

Light to Voltage Converter

The TSL257 is a light-to-voltage converter that integrates a photodiode, operational amplifier, and feedback components on a single monolithic CMOS IC. By providing high sensitivity, low dark offset, and low noise, low levels of light can be measured with significantly increased accuracy. And, speed isnęt sacrificed. The output voltage of the converter is directly proportional to light intensity (irradiance) on the photodiode.

A unique architecture gives the device a high level of sensitivity (responsiveness to light) that provides a transimpedance gain of 320 MW. At 470 nm, the typical irradiance responsiveness is 1.3 V with an output rise and fall time of 160ęs. This optical converter is well suited for use in smoke, mark, and color detection applications as well as in proximity sensors and ambient light systems for contrast control.

The device has improved offset voltage stability and low-power consumption. To simplify system dark-level correction, the TSL257 is factory-trimmed for small positive offset. It is gain trimmed for improved output voltage tolerance, and the output swings rail-to-rail.

The TSL257 is supplied in a clear plastic package with an integral lens. It costs $0.77 in 1,000-piece quantities.

TAOS
(972) 673-0759
Fax: (972) 943-0610
www.taosinc.com

02-01

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