Single-stage LED driver with low bus voltage

A single-stage driver is proposed. The LED driver is obtained by integrating an interleaved boost circuit and an LLC resonant converter. Since the interleaved circuit is adopted here, the input voltage is divided into two parts, each part sharing with one switch of the LLC resonant converter forms a boost circuit in discontinuous mode, and the power factor correction function and low bus voltage are realised. Since the LLC resonant converter is adopted, the converter works in soft switching state, which increases the efficiency of the system. A 100 W prototype is achieved to prove the analysis of the LED driver, and the efficiency of the LED driver is as high as 91% in full load.