A LED driver with switched capacitor

The paper proposes a switched-capacitor converter fed at 24 V to drive power light emitting diodes (LEDs). In contrast to conventional constant dc current drivers, the current pulse is provided by this switched-capacitor. In the present driver, the capacitor is charged and discharged through the output and the current flow direction is controlled by switches. Based on the charge control analysis, the effects of switching devices on the proposed converter are discriminated and evaluated. A 5 W converter prototype has been implemented. The experimental results demonstrated the technical feasibility of the proposed converter for LEDs.