IR proximity detector works up to 1m

Inside, it combines an infra-red (940nm) emitter, photo detectors for proximity and ambient light, a signal-processing IC, and an 8bit/16bit ADC.

For ambient light sensing, sensitivity 16bit and up to 0.011375 lux/step, allowing sensing though low-transmittance (dark) lenses as well as clear ones.

Proximity sensing appears to be 8bit, with a built-in DSP intelligent cancelation scheme that is claimed by Mouser, which is stocking the device, to eliminates background light issues.

“The sensor’s integrated long-distance proximity sensor, ambient light sensor, and 940nm infrared-emitting diode (IRED) eliminate the need for additional light barriers and optical alignment of the IR emitter and photo diode,” said Mouser.

An internal persistence scheme lowers the chances of false proximity sensing due to ambient light noise.

Designed to work with a host microcontroller, separate upper and lower thresholds can be set for ambient light and proximity to allow the host to sleep and be woken only when thresholds are crossed.

Use of a 940nm emitter prevents any red glow from the sensor.

Although the LED is integrated, it needs an external driver mosfet, plus a resistor and pulse energy storage capacitor in some applications – application are expected in smart homes, robotics, lighting, and vehicle detection.

Operation is over -40 to +85°C and 2.5 to 3.6V, and package is 8 x 3 x 1.8mm.