Study and Modeling of Cold Cathode Fluorescent Lamps (CCFL)

Being compared with conventional fluorescent lamps, the cold cathode fluorescent lamps (CCFL) have more compact size, longer lifetime and higher light efficiency. Therefore, they have been widely used as illuminating source and background lighting in LCD panel and notebook computers. However, there is lack of a suitable CCFL model which can be used for ballast designer to apply in their designing work. This paper proposes a simple and user friendly CCFL model which can help a ballast designer to predict the electrical characteristics of a CCFL under different operating frequencies and different dimming conditions. The model is developed based on the energy balance equations governing the discharge process of the cold cathode fluorescent lamps. The simulation results show that the model can predict the lamp electrical characteristics accurately under both low and high operating frequency.