Design Of Three Channel White LED Driver IC Based On Boost Architecture

Because LED semiconductor lighting technology has obvious advantages,such as energy saving,green and environmental protection,and so on,it is widely applied into current industry and life.And LED as a back light source has been widely used in mobile phones,portable electronic products and automotive,aircraft instrument panel,and many other fields.Application of LED switching power supply technology development should have high efficiency,low power consumption,high integration,superior features.According to the application of white LED.In this paper,a white LED driver based on boost architecture is designed.Its working frequency is 1.2MHz,input voltage range is 2.7V~18V,highest output voltage can reach 38 V,and its brightness can be adjusted according to external PWM signal.Power supply under voltage protection,overvoltage protection and other functions are internally integrated.The chip can drive three series of white LED light.First,this paper introduces the development of LED at home and abroad as well as the research status,and introduces the background and significance of this research.Then this paper introduces the working principle of the Boost structure LED driver chip and the working principle of the external P WM signal modulation and its characteristics.After construc the overall structure of the chip,the specific functions and working parameters of the chip are set,and the function of the module inside the chip and the structure of the relationship between the various modules are planned.Then the main modules of the chip circuit design,function analysis and simulation are made.In the end,the simulation of the whole circuit is carried out.The simulation results show that the simulation results can meet the design requirements and the parameters of the design.The structure shows that the circuit function can be realized.Finally,plan the chip's layouyt.After layout successfully taped out,The test proves that the chip can work normally,and the work efficiency reach to 92.55%.In high frequency condition,the PWM dimming linearity is very good.