【作者】 张上洋；

【导师】 吴玉广；

【作者基本信息】 西安电子科技大学 ， 电力电子与电力传动， 2008， 硕士

【摘要】 白光LED以其高效、节能、环保、寿命长、易维护等优点,将逐渐取代传统的白炽灯、荧光灯成为新一代照明光源。由于它的电学参数离散性大,并且容易受温度影响,因而需要设计专门的驱动控制芯片来驱动它。本文主要针对一种市电供电白光LED驱动电路中的控制芯片进行设计。该芯片内部集成耐高压功率管,采用峰值电流型PWM控制模式,通过输出电流和电压反馈信号,产生二次反馈电流信号,调节PWM控制器,实现恒流限压或恒压限流功能,从而实现对白光LED的驱动。文中首先根据实际应用设计芯片的整体电路框图,并结合驱动电路,分析它的工作原理。然后,基于Chrt0.35μm CMOS工艺,利用EDA工具Cadence对芯片内部的低压控制电路进行设计仿真,包括:参考电压源、基准电流源、振荡器、欠压锁定电路、过压保护电路、运算放大器、信号前沿隐匿电路、PWM逻辑电路等。接着利用Medici设计了一种耐高压700V的LDMOS功率管。最后简单介绍了一下电路的工艺实现和版图设计,并按照设计规则完成了部分模块版图的设计。更多还原

【Abstract】 White LED is expected to become a new lighting source after the conventional incandescence lamp and fluorescence lamp with its merits including high efficiency、energy conservation、environment protection、long-life time、easy to be maintained and so on. Because its electrics parameters are unstable and sensitive to the temperature,white LED needs to be drived by special control IC.A control IC which is applied in the white LED driver powered by 220V±20% is designed in this paper. There is a high voltage power transistor integrated inside. Peak value current PWM mode is adopted to deal with the current signal(secondary feedback)which is produced by the output current and voltage feedback signal to modulate PWM controller.Thereby,the functions constant current/restrained voltage and constant voltage/restrained current can be realized and then the function to drive LED can be realized too. In this paper,first,the whole frame plot of this IC was designed according to the practice application. In addition,the operation principle of this IC was analysed according to the driver circuit. Second,based on Chrt 0.35μm CMOS process,the low voltage control circuites were designed and simulated by Cadence which is a kind of EDA tools,including voltage and current references、OSC、undervoltage lockout circuit with hysteresis、overvoltage protect circuit、operational amplifier、leading-edge blanking circuit、PWM logic circuit and so on. Third,a 700V LDMOS device was designed by Medici. At the end,the realization of this control IC’s process and layout were introduced,and the layout of some cells were completed according to the design rule.更多还原