A Current Sharing Using Switched-Capacitor ZVS Driver for Power LEDs

Abstract

This paper proposes a switched-capacitor converter to source power light emitting diodes (LEDs). In contrast to conventional constant DC current drivers, the current pulse is provided by switched-capacitor LED driver. In the present driver it is possible to obtain several output circuits, where the capacitor is charged and discharged through the output circuit and the transfer of power from the grid for the LED is controlled by the switch. The effects of switching devices on the proposed converter are presented and evaluated. The experimental results demonstrated the technical feasibility of using the proposed circuit for the parallel association of LEDs, as well as to improve current sharing among LED strings. The proposed circuit driver with two output circuits presented an efficiency of 91%