描述 Description

The LX1973B is a wide dynamic range light sensor with a very low dark current that is optimized for sensing low level light signals that typically occur under dark or darkening outdoor ambient lighting. The LX1973B has been optimized for automotive systems such as headlamp brightness control or rear view mirror contrast control. Its radical (fractional exponent) response when interfaced with an 8 bit DAC can detect levels down to 0.001 Lux or levels as high as 500 Lux. The spectral response of the integrated light sensor closely emulates the human eye so it ignores light such as infrared which emits energy but doesn’t aid vision. This eliminates the need for an Infrared filter required with competitor’s light sensors. The LX1973B internal circuitry consists of a diode array with Microsemi’s Best Eye? processing that provides a nearly perfect photopic light wavelength response curve. The sensor output feeds into a wide dynamic range compression amplifier that provides accurate resolution over five decades of ambient light. The integrated dark current cancellation circuit facilitates accurate sensing of light below 0.01 Lux. The current source output of the LX1973B can be gain scaled using one external resistor. The LX1973B is internally trimmed to an initial accuracy of 5% at room temperature and a light level of 10 Lux. Accuracy of 10% is maintained over the full temperature range (-40 to +85oC). The LX1973B is available in the domed 8-pin MSOP package, standard or reverse mounting Key Features:Nearly Perfect Best Eye? Human Eye Spectral ResponseDark Current < 0.0005 Lux (@ 25°C)5 Decades Compressed Output10% Accuracy Over TemperatureNo Optical Filters Needed??