Minuscule light and proximity sensor provides very high sensitivity

Mouser now stocks the TSL2740 combined ambient light and proximity sensor from ams. Providing exceptionally high sensitivity when detecting ambient light even at millilux-level intensity, the sensor is excellent for smartwatches and wearables, smart home assistants, tablets, smartphones, display backlight control, and medical diagnostics applications.

The device combines an ALS and a proximity light-to-digital sensor that approximates the human eye response to light intensity under changing lighting conditions. The 2mm x 2mm x 0.5mm device provides a broad dynamic range to function effectively in a wide spectrum of lighting conditions, converting light intensity to a digital signal output through a 1.8V I2C interface.

The device delivers proximity sensing by measuring reflected IR light emitted from an external LED. The proximity engine offers automatic ambient light subtraction, as well as offset adjustment registers to offset for unwanted IR energy reflection at the sensor at a range of up to 10cm.

The device’s ALS sensor provides two output channels: a visible channel and an IR channel. The visible channel uses a photodiode with a photopic interferometric UV and IR-blocking filter. The IR channel uses a photodiode with an IR pass filter. Each channel has a dedicated integrating data converter that converts photodiode current into a 16-bit digital output which can be interfaced with a microprocessor.