Control IC Simplifies High-Performance Dimming Designs

Primary-side regulation employed by International Rectifier’s IRS2983 control IC reduces component count and simplifies LED-driver and power-supply design by eliminating the optoisolator and other components needed for fixed-load isolated feedback. Designed for single-stage flyback and buck-boost topologies, the device incorporates a rapid startup circuit that significantly reduces the system’s turn-on time. Other features include high power factor, low total harmonic distortion, and operation over a wide input range. Critical-conduction mode operation, with discontinuous and burst modes at light load plus flexibility, facilitates connection to optoisolated feedback circuitry for more complex designs. The device also integrates overvoltage, cycle-by-cycle overcurrent, and open/short-circuit protection. It supports TRIAC dimming. The IC comes in an SO-8 package.

INTERNATIONAL RECTIFIER