Design and Test of an Innovative LED Driver Based on a Mixed Digital/Analog Architecture

There is a growing demand to limit energy consumption in Western countries. Actual challenges are to provide products compatible with classical lamp socket and voltage. Emerging technologies are Compact Fluorescent Lamps (CFL) and LEDs, but there are some drawbacks mainly concerning CFL and compatibility with dimmers. In this paper we present the design of an innovative LED driver integrated circuit based on mixed analog/digital control. We present also the methodology for integrating the digital computation by means of a Field Programmable Gate Array (FPGA) based development platform allowing to precisely adapt and test the parameters needed for maximum efficiency and dimming compatibility before integration into an IC. The VHDL-based design for the digital part allows final implementation by means of synthesis to either an FPGA or a full custom netlist. Experimental results are given to demonstrate the validity of the proposed circuit and methodology of implementation.