A Single-Stage LED Driver Based on Double LLC Resonant Tanks for Automobile Headlight With Digital Control

A novel single-stage light-emitting diode (LED) driver with high voltage gain for LED automobile headlight is proposed in the paper. The converter is made up of two parts, which are the boost cell and double LLC cell, and the two parts are integrated by sharing the switch. Since the number of the system components is reduced by integrating the switches, the cost decreases. The boost circuit works in the continuous conduction mode with double voltage gain, and the double LLC cell connected in series can decrease the peak current and increase the efficiency of the system. A 30-W prototype is proposed in the lab, with 30 high-brightness LEDs connected in series. The experimental results well confirm the theoretical prediction, and the efficiency of the system for the full load is higher than 92%.