一种用于大电流LED驱动的高侧电流检测电路

摘要

针对 LED驱动中宽输入电压范围和高精度检测的要求，提出了一种高侧电流检测电路.采用互补金属氧化物半导体(CMOS)器件作为放大器，通过检测串联在电路中的采样电阻两端电压差的大小，用滞回控制方法控制电流回路的通断，能精确控制0.5~5 A 的输出电流，在5~40 V 电压下达到了3%的检测精度.该电路结构简单，通过0.6μm 5~40 V CMOS-双重扩散金属氧化物半导体(CDMOS)工艺流片验证，芯片测试结果表明电路工作良好，能满足要求.%This paper proposes a high-side current sensing complementary metal oxide semiconductor (CMOS)circuit which is ap-plied to high-brightness LED drivers.By detecting the voltage drop of a sense resistor in series and applying hysteresis control strate-gies,it controls the on-off of the current loop and has achieved a 3% accuracy while the output current varies from 0.5-5 A at 5-40 V input voltage.The circuit has been implanted in 0.6μm 5-40 V BCDMOS process,and the test shows that the circuit exhibits a satis-factory performance and can meet requirements.