High-power-factor electronic ballast for T5 fluorescent lamp with multiple dimming interfaces

Owing to the perception of high-efficiency and comfortable lighting systems possess better energy-saving effect as well as the positive impact on the health and performance of people, the demand of dimmable electronic ballasts for fluorescent lamps is increasing rapidly. A high-power-factor electronic ballast with varied dimming interfaces for T5 fluorescent lamps is devised in this paper. With functionality of wide dimmable range, the proposed ballast provides flexible and friendly dimming mechanism for application in modern lighting system. The developed ballast consists of an EMI filter, an active power factor correction (PFC), an inverter power stage with a resonant tank, and a fully isolated dimmer with different control interfaces. By means of wired or wireless transmission protocol, the industrially standard 0 to 10 Vdc control signals are generated to tune the lamp luminance. Performance and effectiveness of the proposed dimmable ballast on T5 28W lamps are demonstrated via a prototype experimental setup.