Smallest ambient light sensor for wearable products

April 30, 2015 // By Graham Prophet
ams claims to have the world’s smallest ambient light sensor, which it designed for next-generation thinner wearable products. Its integrated on-chip interference filters reject infrared producing a near-photopic response

The TSL2584TSV ambient light sensor (ALS) coes in a through-silicon via (TSV) package which has a footprint of just 1.145 x 1.66 mm and a height of 0.32 mm.

In display management applications, automatically controlling the backlight intensity with an ALS ensures the best possible user experience while extending battery life. The new TSL2584TSV’s outline and height are approximately half the size of competing ALS devices, leading to the claim of smallest ALS.

ams’ has developed its wafer fabrication expertise to include TSV packaging technology as part of its light sensor portfolio. This TSV package technology improves performance by eliminating use of wire bonds and provides a direct connection from the device I/Os to a solder ball. TSV enhances the device reliability performance with a Moisture Sensitivity Level-1 standard rating, improves Humidity Temperature-Cycling performance while minimising corrosion resistivity.

The TSL2584TSV’s near-photopic response produces a highly accurate lux measurement even when mounted behind dark glass. Advanced fabrication technology and the ability to accurately deposit interference filters directly onto the silicon results in a superior performing ALS. Filtering out unwanted IR light enables the sensor to more accurately measure the ambient light thus producing a near-photopic response.

The TSL2584TSV is priced at $0.58 (1,000)

ams; www.ams.com/ambient-light-sensors/TSL2584TSV