一种双环路反馈控制电荷泵LED驱动器设计  

Design of a novel LED driver for dual loop charge pump

作　　者：王辉[1] 王松林[1] 郭宝龙[1] 叶强[1] 

机构地区：[1]西安电子科技大学机电工程学院,陕西西安710071

出　　处：《华中科技大学学报（自然科学版）》2010年第11期11-15,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(60572152)

摘　　要：针对电荷泵LED驱动器环路控制在不同工作模式下存在较大的输入噪声和较大的输出电压纹波的问题,基于TSMC0.6μmBCD工艺,设计实现了一种电压外环和电流内环的双环路反馈控制方案.其中多增益工作模式的电压外环有效地提高在不同输入电源电压下的效率;电流内环利用电流镜代替传统的可调电阻,实现了低噪声线性控制方式.两种控制环路的结合,既可有效减小电源电流的峰值,又可降低电荷泵的输出纹波,从而降低输入输出噪声.经留片测试,对于正向导通电压为3.4V的LED,电源电压在3.0～4.4V变化范围内,输出电压为3.6V,输出电流为400mA的条件下,所设计电路的最高效率可达90.1%.To overcome high input noise and big output ripple under different operational mode in the charge pump of LED driver,a dual loop feedback control solution is designed and realized based on TSMC 0.6μm BCD process.Multi gain operational mode of the voltage out loop,which can improve the efficiency under different voltage input.By replacing traditional adjustable resistance with current mirror in current inner loop,the low noise linear control mode is achieved.By combining the two control solution,not only the peak current of power can be effectively decreased,but also the output ripple of the charge pump,thus the input and output noise be brought down.The experiment result shows that the proposed control solution is feasible.The designed circuit can reach up to 90.1% efficiency under the condition of the LED of forward turn-on voltage 3.4V,3.0～4.4Vvoltage swing, 3.6Voutput voltage and 400mA output current.

关 键 词：电荷泵 LED驱动器 电压环 电流环 低电源噪声 双环路反馈 

分 类 号：TN432[电子电信—微电子学与固体电子学]