Novel electronic ballast with integrated digital power factor controller

The business of nondimming electronic ballasts for fluorescent lamps is dominated by strong requirements for cost reduction. Sub micron mixed signal ASIC technology in the lighting business is already state-of-the-art. This technology offers a lot of advantages like high complexity on small silicon area. This paper presents an novel nondimming ballast control IC with integrated digital power factor correction. The IC is fabricated in state-of-the-art 0.35 μm standard CMOS process and fits into a SOIC20 package. The IC supports the classical ballast topology with a preconverter-stage, i.e. a boost type topology, and as a DC-AC-converter the classical half-bridge. The ASIC provides all the required features to drive and control the different families of fluorescent lamps like linear and compact lamps. Focus of this paper is on the integration of the digital preconverter in boost topology.