LED controller has two-color mixing with triac dimmer compatibility

May 30, 2012 // By Christoph Hammerschmidt
Cirrus Logic has introduced its second family of digital LED controllers with digital TruDim dimmer compatibility technology designed to accelerate worldwide adoption of LED retrofit bulbs. In addition to providing near 100 percent compatibility with the world's installed base of dimmers, the new CS163X family provides two-channel LED color mixing capabilities. This allows LED bulb manufacturers to more efficiently create warm, natural light quality while also lowering the cost barrier for two-channel LED retrofit bulbs.

The CS163X family enables improved color quality at up to 30 percent greater efficacy than with single-channel white LEDs. An innovative digital architecture provides the CS163X family with the ability to control two LED strings using components typically used to control a single LED string, resulting in lower system costs compared to today's two-channel solutions. In addition, the CS163X incorporates powerline calibration technology, allowing manufacturers to calibrate bulb characteristics such as light output and color temperature by sending commands via the AC mains terminals during the final manufacturing stage. This patent-pending technology allows manufacturers to utilize LEDs with a wider variation in performance characteristics, resulting in lower LED costs while maintaining consistency in light output and color temperature from bulb to bulb.

“Cirrus Logic's CS163X two-channel, triac dimmable digital LED controller is a breakthrough in digital controllers and an ideal system solution for our Brilliant Mix technology,” said Horst Varga, Applications Engineering, OSRAM Opto Semiconductors. “CS163X’s high level of integration and performance enables many new opportunities for the Brilliant Mix technology in LED retrofit applications requiring high color rendering index (CRI) and high efficacy. The combination of these technologies will accelerate the growth of LED bulbs that match the natural light color quality performance of today’s incandescent and halogen bulbs.”

Cirrus Logic entered the LED market in March 2012 with the first product in its roadmap of LED controllers, the CS161X family, which focused on solving dimmer compatibility issues. Fundamental to Cirrus Logic’s LED product family is the company’s digital TruDim technology, which was the result of a three-year investment in triac interface algorithms, LED driver topologies and system architectures. TruDim digital intelligence allows the controller to identify the type of dimmer in use and adapt its dimmer compatibility algorithm to provide smooth dimming in much the same way the consumer has come to expect from decades of using incandescent light bulbs.

“Cirrus Logic’s roadmap of digital LED controllers is