How to design a dimming fluorescent electronic ballast

Dimming fluorescent lamps is an attractive feature that provides mood and brightness effects as well as having tremendous energy savings potential. Designing a dimmable electronic ballast, however, is a complicated and challenging task. This paper presents an overview for designing a dimming electronic ballast for a T5 35W lamp. Lamp requirements, dimming control methods, and resonant output stage design are all discussed in this paper. A new ballast design software program is also demonstrated which greatly aids with the design of the dimming ballast and generates the necessary schematic and bill of materials for prototyping. Finally, a fully-functional prototype is built, tested and compared against original design results.