Light to digital sensor delivers optical power meter functionality

Offering a wide spectral bandwidth, flexible and automated light measuring over a 23-bit effective dynamic range, and a simplified software and set-up configuration, this low-power optical sensor is ideal for use in optical spectral systems that require detection of a variety of wavelengths, such as optically-based diagnostic systems, or even as a low-power, battery-operated wake-up sensor.

The sensor is an ambient light sensor (ALS) with a digital output integrated circuit. The OPT3002 features a wide spectral bandwidth that measures light within the device spectral range of 300 nm to 1,000 nm.

Using the device’s built-in, full-scale setting feature, the OPT3002 can take light measurements from 1.2nW/cm² up to 10mW/cm² without the need to manually select the full-scale ranges.

This built-in functionality enables capturing of light measurements over a 23-bit effective dynamic range, with results compensated for dark-current effects and other temperature variations.

The OPT3002 captures measurements in either a continuous or single-shot fashion. The optical sensor measures the ambient light and reports the optical power readings directly from its two-wire, I²C- and SMBus-compatible serial interface.

The interrupt pin system can also summarise measurement results with one digital pin. With fully-operational power consumption as low as 0.8 μW at 0.8 SPS on a 1.8V supply, the OPT3002 Light-to-Digital Sensor can be incorporated into a broad array of low-power, sensor-based applications, including security detection systems, system wake-up circuits, medical and scientific instrumentation, lighting controls, tablet and notebook computers and home automation.

The sensor is available in a compact, 6-USON package that measures only 2.0 mm × 2.0 mm × 0.65 mm. To evaluate the OPT3002 under various conditions, the device is also supported by the OPT3002EVM ambient light sensor evaluation module.

The OPT3002EVM features a small form factor module based on two PCBs (a data acquisition board and test board), includes intuitive GUI software, and is designed with 100mil-spaced test points for easy experimentation with external controllers.