Single-switch non-resonant electronic ballast to integrate a low-cost fluorescent lighting system

The aim of this study is to analyse the application to fluorescent lighting of a non-resonant electronic ballast, focusing on a specific low-cost single-switch topology. Its complete mathematical analysis, which has not been fully explored in the past, and its practical implementation as a DC-fed electronic ballast unit are provided. The ballast here presented was successfully prototyped and is capable of pre-heating, igniting and driving two or more fluorescent light bulbs associated in series, having also an intrinsic protection against broken filaments and lamp absence. Furthermore, it relies solely on a single power switch and a relatively small-sized inductor per lamp, plus simple op-amp-based control circuitry. An additional protection circuitry is also presented in this study, for protecting the power switch against lamp faulty conditions. Good efficiency was achieved with ballast prototype and cost effectiveness for the proposed lighting system is demonstrated in this work.