Design of an inductor-based wled driver using clean energy power supplies

For mobile back-lighting applications, a dual-input white LED (WLED) driver using a bi-direction buck-boost converter is proposed in this paper. The proposed driver has two input terminals: lithium battery input Vin1 and solar-cell input Vin2 Unlike conventional drivers using boost converters, step-up SC DC-DC converters, and so on, the proposed converter drives the anode and the cathode of LEDs by using the solar-cell's voltage and the negative stepped-down voltage, respectively. Furthermore, by converting solar energy, the proposed converter can charge the lithium battery when the LED back-light is off. Therefore, the proposed converter can realize long battery runtime. The validity of the proposed converter is confirmed by simulations and experiments. ICIC International © 2010 ISSN.