220W Adapter For LCD Television

With the development of technology and the quality of people's lives, traditional CRT television is being replaced by high-performance televisions such as LCD and PDP. Because of the different operating principle, these televisions raise different requirements for their adapters. Besides, the short of energy supply makes governments enact standards to restrict adapters in efficiency and stand-by loss. These all issue great challenges for adapters' studying.This paper focuses on a 90V～265V AC input and 19V/11.6A DC output adapter for LCD television. The two-stage structure of PFC+ LLC resonant converter is chosen based on the comparison of several schemes. In this paper, deduction of components' values in power stage of CRM mode PFC and design of controlling circuit based on L6563 are discussed firstly. And then, the principles of LLC resonant converter are introduced. The performance of LLC resonant converter is analyzed using fundamental approximation method in detail. The limitation of fundamental approximation method is pointed out, and a combination of fundamental approximation analysis and simulation is presented to determinate the values of resonant tank components. The design of controlling circuit is also referred. A prototype of a 90V～265V AC input and 19V/11.6A DC output adapter is completed, and the experiment results verify that scheme can fulfill the demands of LCD television entirely. Finally, through the analysis of experiment results, possible improving directions are pointed out.