基于镜像电流镜的LED线性恒流驱动电路设计

Design of linear LED current driver using current mirror circuit

本论文主要阐述了可用于车用仪表背光灯的基于镜像电流镜的LED线性恒流驱动芯片设计,在分析设计车用LED背光灯线性恒流驱动电路时采用串联镜像电流镜及并联镜像电流镜驱动电路的优缺点基础之上,设计了带隙基准稳压电源模块及电压降低转换模块,并推出一种新颖的具有高精度、高输出阻抗的并联镜像电流镜驱动电路,该驱动电路不需要任何把电压转换为电流的电阻,因此芯片相对容易实现并且实现的芯片面积相对较小,最终通过电路仿真测试加以验证。

This paper presented how to design LED linear current driver using current mirror method for backlight of automobile panel,the advantage and disadvantage of parallel and series LED driver is analyzed.The bandgap reference block and voltage down convert block is designed,a novel scheme is present which can enhance the output current precision and promote the output resistance,which is no need to use any resistance,so the chip can be fabricated easily and have small area.The simulation result is checked and confirmed it.