Design And Implementation Of Large Size Multi-lamp Backlight Driving And High Power Integration Technology Of LED TV

LED backlight driving circuit system is the key to determine the reliability of large size LCD TV, color temperature, life and environmental protection and energy saving. In this paper, reliability, high efficiency for the purpose, the circuit topology and the circuit system is analyzed, the advantage of the application of innovative LLC topology in LED backlight driver, and integrating design with AC/DC power supply circuit, to drive the LED backlight source of high reliability, high efficiency. Then the board level implementation and test validation detailed on the designed circuit system.The innovations lie in the following aspects:System architecture:the LLC circuit topology and high work efficiency, output, constant current dual drive LED backlight using capacitance balance technology innovation, change the traditional mode of two on the required two voltage driving system status, improve the stability and accuracy of the LED lamp constant current control,and the realization of the use of remove the electrolytic capacitor, electrolytic capacitor electrolyte to eliminate bottlenecks due to high temperature evaporation and affect the life, thus greatly improves the reliability of the system, and LED drive efficiency can be increased to more than92.5%.The circuit of low power consumption high efficiency design:first, through the use of low standby power consumption function of the flyback NCP1271chip design, in the standby condition with a frequency hopping mode to reduce the standby power consumption, realize the standby power consumption is less than the "Energy Star"0.5W standard. Secondly, pre active PFC circuit using effective power factor correction, will improve the power factor power input to close to0.99, with the LLC resonant circuit, stable and high efficiency, energy saving system.Backlight drive:TL431built by the protection of the main circuit, the over-current protection, over voltage protection, open circuit protection, short circuit protection, over power protection can reliably realize.The backlight system protection problems in time. prevent accidents.This paper introduces the design and implementation of LED backlight driving circuit system has certain reference value for the research and application of LED drive circuit, and has the certain application value and economic value of LED backlight LCD TV products.