Tutorial

Summary form only given. With advances in solid-state lighting, high brightness light emitting diodes (LEDs) have been widely adopted in general lighting applications, due to high luminous efficacy and long life expectancy. We are now entering a new era of lighting history, shifting from traditional discharge lamps to solid-state lamps. Thus, retrofit LED lamps for traditional lighting infrastructure would facilitate and accelerate market adoption of LED technologies. More importantly, it is an environmentally-friendly solution, as it is unnecessary to change the lighting infrastructure. In this tutorial, the presenter will deliver a talk related to retrofit LED lighting technology. The presentation will start with the operating principle of typical discharge lamp ballasts. Then, the requirements and considerations of driving LEDs with discharge lamp ballasts will be discussed. Finally, a technology utilizing daisy-chain transformers for current balancing multiple LED strings in a high-power LED lamp will be presented.