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.