Study and implementation of hybrid dimming inverter for T5 fluorescent lamp

In this paper, a hybrid dimming inverter for T5 fluorescent lamp is analyzable and designed. By using the digital and analog hybrid dimming, the current stress of switches is reduced, and the dimming range can be extended. A high-frequency inverter with DC 400V voltage source to drive a single T5 28W fluorescent lamp is implemented. The preheating, starting-up function, and hybrid dimming control circuit with a soft-transition operation are implemented. Also, the effectiveness of analog, digital and hybrid dimming are compared. They show that the current stress of switches is reduced by 10% at lightly load, the dimming range is 100% to 20% and the efficiency is up to 90% at full load condition.