Technology Research Of120W3Output LED Driver

With the outbreak of the energy crisis in recent years, energy conservation is increasingly mentioned important position. Lighting energy consumption proportion is relatively large, with the development of the LED industry in recent years, the lighting gradually began to adopt energy-saving, environmental protection and high-life’s LED products.Because of LED’s special photovoltaic characteristics, it can not use AC mains directly, so LED requires a dedicated drive for driving. At the same time in order to maintain the characteristics of the LED energy-saving and high-life, LED drivers need to achieve high efficiency and high-life.The paper illustrates the principle, the development and characteristics of the LED and LED driver characteristics and driver programs are discussed. Discusses in detail the key technology of the power factor correction technology, the half-bridge LLC technology, multi-output technology, conduction disturbances suppression.On this basis, designed and produced a120W3-output LED street lamp driver. The program uses critical mode active power factor correction technology to make the power factor to achieve a higher value, and provides a stable input voltage to the next circuit at the same time. And then use the structure of half-bridge LLC to do DC-DC transform, the output constant voltage using a TL431, and provide a stable voltage input to the multiple outputs stage. Finally, using multiple sets of Boost structure for multiple outputs, while taking advantage of the dual op amp AP4310to accurate constant current output. The design uses a half-bridge LLC structure to achieve switching tube’s zero-voltage turning-on and freewheeling diode’s zero current turning-off, greatly reducing the energy loss in the switching process. And stability and electromagnetic compatibility problems encountered in the design, analysis and proposed solutions. The results obtained through prototype testing to comply with the relevant regulations and standards. The paper describes120W multi-channel output LED street lamp drive prototype testing, collected and analysis of the waveform of the key points in the circuit.The test results show that the drive can work in wide voltage conditions. EMC compliance, full load power factor greater than0.97, the machine efficiency reached93.3%. Better achieve the design goals.