Single-Stage LED Driver Based on the Totem-Pole Rectifier Requiring Reduced DC-Bus Voltage

A nonisolated single-stage light-emitting diode (LED) driver based on the totem-pole rectifier requiring reduced dc-bus voltage is introduced in this article. The proposed topology requires a low component count and exhibits high efficiency. Charge-pump and resonant capacitor concepts are used to achieve reduced LED current ripple, high-power factor, and dc-bus voltage levels close to the input voltage peak value. Experimental results of two built prototypes operating with input voltages of 127 and 220 V-rms, output voltage of 90 and 140 V, and rated power of 45 and 70 W, respectively, are presented and validate the analysis carried out. The measured dc-bus voltage at rated power condition is 220 V for an input voltage of 127 V-rms 360 V for 220 V-rms, demonstrating the capability of the proposed circuit to guarantee reduced dc-bus voltage levels. In addition, both prototypes exhibited efficiencies up to 95.2%, therefore indicating the potential of the proposed LED driver for high-efficiency operation.