基于可控开关电容充放电平衡的多路LED驱动器  

Multi-Channel LED Driver Based on Charging and Discharging Balance of Switch-Controlled Capacitor

作　　者：曾君[1] 孙伟华 刘俊峰[1] Zeng Jun;Sun Weihua;Liu Junfeng(School of Automation Science and Engineering South China University of Technology Guangzhou 510640 China)

机构地区：[1]华南理工大学自动化科学与工程学院,广州510640

出　　处：《电工技术学报》2017年第18期267-275,共9页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金项目(61573155);广东省自然科学基金(2016A030313508);广东省科技计划项目(2016A010102007)资助

摘　　要：在多路LED均流方案中,基于电容电荷充放电平衡的均流方案具有简单、精确、成本低、可靠性高等优点。结合可控开关电容(SCC)技术和电容电荷充放电平衡技术提出一种多路LED驱动电路。详细分析SCC的工作周期、稳态工作模态以及简化等效电路,得到了SCC等效电容对LED驱动电流的调控曲线。最后搭建了一台四路输出、每路(180~350m A)可调光LED驱动样机,样机可以实现模块内两路LED、模块间四路LED的精确均流,同时模块间通过SCC调控可实现独立调光,具有良好的调控性能和可拓展性。Among the current sharing schemes of multi-channel LEDs,the scheme based on charge and discharge balance of capacitor is simple,accurate,low cost and high reliability.In this paper,a novel multi-channel LED driver topology is proposed,combined the switch-controlled capacitor(SCC)with the charge and discharge balance of capacitors.The operating period of SCC,the working mode of the module and the simplified equivalent circuit are analyzed in detail.The control curves of LED drive current versus the equivalent capacitance are obtained.A four-channel LED driver prototype was built up with good current sharing performance and expansibility.The controllable range of drive current is from180mA to350mA per channel.The prototype can achieve accurate current sharing of two-channel LED within a module,accurate current sharing of four-channel LED within different modules,and the independent dimming of different modules.

关 键 词：LED驱动电路 可控开关电容 充放电平衡 均流 可拓展性 

分 类 号：TM923[电气工程—电力电子与电力传动]