Low Power, <100 Lux Optimized, Analog Output Ambient Light Sensor

Device is no longer available or supported, and production has been discontinued.

Product Status: EOL


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 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 2mmx2.1mm ODFN plastic surface mount package. Operation is rated from -40°C to +85°C.


  • Square root voltage output
  • 0.01 lux to 100 lux range
  • 1.8V to 3V supply range
  • Close to human eye spectral response
  • Fast response time
  • Internal temperature compensation
  • Good IR rejection
  • Low supply current
  • Operating temperature range -40°C to +85°C
  • 6 Ld ODFN: 2mmx2.1mmx0.7mm
  • Pb-free (RoHS compliant)


 Block Diagram


Basic Information
Production Status
Peak Spectral Sensitivity
550 nm
VS (min)
1.8 V
VS (max)
3.0 V
Supply Current @ EV =100Lux
23 µA
Lux Range (max) (lux)
Output Voltage @ EV=100Lux
1.85 V
Dark Voltage @ EV=0Lux
.95 mV
Rise Time
95 µs
Fall Time
155 µs
Qualification Level
Delay Time, Rising Edge (μs)
350 @ 100Lux
Delay Time, Falling Edge (μs)
250 @ 100Lux
Package Dimensions (mm)
Pb Free?
Enable Pin?
Temperature Range
-40 to +85

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