ISL29112

The ISL29112 is a low cost, light-to-voltage silicon optical sensor combining a photodiode array, a non-linear current amplifier, and a micropower op amp on a single monolithic IC. Similar to the human eye, the photodiode array has peak sensitivity at 550nm and spans the wavelength range of 400nm to 600nm, rejecting UV and IR light. The input luminance range is from 0.01 lux to 100 lux. The integrated non-linear current amplifier boosts and converts the photodiode signal into a square root output format, extending dynamic range while maintaining excellent sensitivity in dimly lit conditions. As such, the part is ideal for measuring incident daylight when mounted behind heavily smoked bezels used around displays or behind mirrors. The device consumes minimum power. A dark current compensation circuit minimizes the effect of temperature-dependent leakage currents in the absence of light, improving the light sensitivity at low lux levels. The output gain has been optimized to require a relatively low value external bias resistor that falls within recommended automotive EMI limits. The built-in 1μA op amp gives the ISL29112 an output voltage driving advantage for heavier loads that can drive an ADC directly. The ISL29112 is housed in an ultra-compact 2mm x 2.1mm ODFN plastic surface mount package. Operation is rated from -40 °C to +85 °C.