Modeling of Cold Cathode Fluorescent Lamps (CCFLs) With Realistic Electrode Profile

Compared with conventional fluorescent lamps, the cold cathode fluorescent lamps (CCFLs) are more compact in size and have a longer lifetime. Therefore, they are widely used as an illuminating source and background lighting in liquid crystal display panels and notebook computers. However, a suitable CCFL model that can be used by ballast designers is lacking. This paper proposes a simple and user-friendly CCFL model that can help a ballast designer to predict the electrical characteristics of a CCFL under different operating frequencies and dimming conditions. The model is developed based on the energy balance equations governing the discharge process of CCFLs and the prediction of the amplitude and shape of the cathode voltage drop in CCFLs. The simulation results show that the model can accurately predict the lamp´s electrical characteristics under both low and high operating frequencies.