Dimmable High Power LED Driver Designs

With the development of science and technology, the lighting industry is changing rapidly. Nowadays, the LED, a new product in the lighting industry, is gradually replacing the current mainstream incandescent bulls or energy-saving lamps. On one hand, how to design high power LED drivers with high efficiency, power factor and reliability has been one of the hottest issues at present. On the other hand, in order to be more energy saving and environmental friendly, and to increase the life span of the driver, dimming technology has been paid much attention to these questions. Therefore, for the LED lighting industry, research on the high power LED driver with dimming function shows great significance and very high application value.Aiming at the issues mentioned above, the main contents of this paper are as follow:(1) The main theoretical basis of this design is analyzed, including:theoretical study of the power factor correction technology, analysis of the working conditions and principle of the LLC resonant half-bridge circuit, analysis on the working states of the circuit in different parameters with the FHA model.(2) Design the APFC based on L6563——the Active Power Factor Correction circuit, including the design of peripheral circuit and component parameters. The design improves the efficiency of the driver and reduces the interference driver on the grid effectively by optimizing the key paraments.(3)Design the LLC resonant circuit based on L6599.The design improves the efficiency of the driver by the application of zero-voltage and zero-current switching technology and optimizing the paraments.(4) Design the dimming including the design of output control circuit based on TSM101and dimming control circuit. It ensures the stability and accuracy of the output power by optimizing the traditional dimming control circuit. This design realizes two dimming methods of the analog and the degital. Users can choose the appropriate one according to different needs.(5) A prototype of2dimming modes is made according to the parameters, which maximum output voltage reaches40V and maximum output current reaches3A. The paper analyzes the experimental data and waveform, demonstrating the correctness of theoretical analysis and the feasibility of design method. Moreover, some suggestions are proposed for further study of the design.