Single Input LC Series Resonant Converter Based High Brightness Light Emitting Diode Driver with ZVS
Abstract
This work proposes a high brightness light emitting diode (HB-LED) driver circuit based on a full-bridge LC series resonant converter with series DC bus for low power applications with a dimming feature. The proposed configuration consists of full-bridge LC series resonant converter with a series DC bus. The idea behind the concept is to supply the light emitting diode (LED) threshold voltage directly from the constant DC bus - and the control voltage, which is used for current regulation, is supplied through a full-bridge LC resonant converter. Since the control voltage responsible for current regulation is only processed by the full-bridge series resonant converter, the conduction loss is less even if several LED strings are connected to the same converter. The proposed HB-LED driver is characterized by low switching loss, reduced component count, high efficiency, and reduction of output electrolytic capacitor. Further, double pulse width modulation (DPWM) dimming control is designed and used to control the average output currents. The proposed high brightness light emitting diode (HB-LED) driver circuit based on a full-bridge LC series resonant converter is simulated using Orcad/PSpice software. The theoretical analysis and predictions of the proposed full-bridge series resonant converter-based HB-LED driver is in close agreement with the results obtained.
