Solution to maintain colour stability and lumen output

The AS7220 Smart Lighting Manager from ams uses closed-loop sensing to maintain accurate correlated colour temperature (CCT) and lumen output. The company claims the solution could enable a new generation of higher quality LED-based lamps and luminaires.

The AS7220 combines a precise calibrated-for-life colour sensor with an intelligent cognitive lighting engine for standalone closed-loop maintenance of the output.

The result is a luminaire which automatically adjusts for the colour shift and lumen depreciation of LEDs as a natural result of aging, operating temperature changes and driver variation over lifetime.

By employing sensor-driven algorithms, the AS7220 is said to enable the manufacturer to use a more loosely CCT- and flux-binned range of cool-white and warm-white LEDs to achieve a high and stable quality of light.

Control of the power supplied to LED strings is implemented via digital switching of multichannel power supplies or through a combination of PWM current steering with an analogue or digital output to standard single-channel 0 to 10V or PWM-input dimming ballasts or drivers.

The AS7220 is pre-configured for optional operation to provide for autonomous daylight harvesting using standard 0 to 10V dimming inputs. The Smart Lighting Manager also provides a direct interface to standard occupancy sensors to enable intelligent dimming control and energy-saving schemes.

Accurate and stable CCT control is enabled by the AS7220’s embedded tri-stimulus CIE XYZ colour sensor, which directly maps the sensor channel data to the CIE 1931 colour space.

According to the company, nano-optic interference filters deposited on the die of AS7220 devices offer high stability and virtually no degradation over time and temperature. Measures 4.7 x 4.5 x 2.5mm, the sensor system’s LGA package includes a built-in aperture with a ±20.5° field of view.

Peggy Lee