Circuit Design and Performance Analysis of CCFL Dimming Controller With Frequency Modulation

  • Kim, Cherl-Jin (Department of Electrical Engineering, Halla University) ;
  • Ji, Jae-Geun (Department of Electrical Engineering, Halla University) ;
  • Yoon, Shin-Yong (Department of Electrical Engineering, Dongguk University)
  • Published : 2004.12.01

Abstract

The CCFL dimming control methods are generally used lamp current regulation or average current adjustment method feeding the CCFL inverter. Inverter operation frequency is higher than resonant frequency for safe operation. In this study, we design the half-bridge type series and parallel resonant converter circuit that switches at variable frequency modulation methods to control the output power. This method has advantages such as low EMI and reduced harmonics, and it is convenient for dimming control using a microprocessor. The validity of this study is confirmed from the simulation and experimental results.

Keywords

References

  1. Joel A. Donahue, P.E. and Milan M. Jovanovic, ‘The LCC Inverter as a Cold Cathode Fluorescent Lamp Driver’, APEC 1994, pp.427-433
  2. Louis Robert Nerone, ‘Design of a 2.5-MHz, Soft- Switching, Class-D Converter for Electrodeless Lighting’, IEEE Trans, On Power Electronics. Vol 12, No 3, May 1997
  3. M.Jordan, J.O'conner, ‘Resonant Fluorescent Lamp Converter Provides Efficient and Compact Solution’, Unitrode application note U-141
  4. S.W.Lee, D.Y.Ko, D.Y.Huh and Y.I.Yoo ‘Simplified Control Technique for LCD Backlight Inverter System Using the Mixed Dimming Method’ IEEE Trans, On Power Electronics
  5. S.A.EI-Hamamsy, ‘Design of High-Efficiency RF Class-D Power Amplifier,’ IEEE Trans, On Power Electronics. Vol 9, No3, pp. 297-308, May 1994