LED Driver ICs Deliver Flicker-Free Dimming, Hot-Plug Support
Wed, 02/09/2011 - 7:22am
iWatt, Inc., announced two primary-side-regulated, leading- and trailing-edge-dimmable, AC/DC digital PWM controllers targeting 100 V/230 VAC offline LED lighting applications. Designed for isolated or non-isolated LED drivers used in incandescent replacement lamps including both space-constrained (GU10, MR16) and larger (A, PAR) types, the iW3612 (3 W to 25 W) and low-power iW3602 (3 W to 10 W) incorporate features to ensure long life, power efficiency, reduced size and component costs, and flicker-free compatibility with existing wall dimmers worldwide. Both LED driver ICs are pin compatible with the previous-generation iW3610, but offer wider dimmer compatibility and introduce new hot-plug support, where the user can swap the LED engine without recycling the input power for the LED driver. Intelligent digital algorithms automatically detect all types of dimmers or a lack thereof for seamless operation, including both leading-edge (TRIAC style) and trailing-edge dimmers. In the rare case of an unsupported dimmer, safe mode shuts it down. The devices allow smooth, flicker-free dimming from 1 percent to 100 percent with tight +5% LED current regulation which prevents flicker from noisy line voltage. The company’s AC/DC power conversion ICs feature a digital feedback and control loop versus analog, which is transparent to designers and requires no programming or GUI.