摘要
提出了一种用于低压差稳压器的过流保护电路,该过流保护电路基于SMIC 180 nm CMOS工艺,采用1.8 V供电电源,在不影响原有LDO功率管管压降的同时,提高了输出电流的采样精度,限制LDO功率管的最大输出电流及LDO输出电压过低时降低功率管的电流输出。达到过流限后,负载电流与功耗下降比成正相关,负载电流越大,整体功耗下降越多。随着负载电流的增加,至触发电流折返之前,功耗下降比由0%开始逐渐提高至20%~30%;电流开始折返后,功耗下降比由20%~30%开始逐渐提高至99%。在负载电流未达到电流折返的临界点时,LDO瞬态性能不受影响;在负载电流达到电流折返临界点时,输出电压下降约500 mV,但其余瞬态性能不受影响。
This paper proposes an overcurrent protection circuit for low dropout regulators.The overcurrent protection circuit proposed in this paper is based on the SMIC 180 nm CMOS process and uses a 1.8 V power supply to improve the sampling accuracy of the output current,limit the maximum output current of the LDO power tube and reduce the current output of the power tube when the LDO output voltage is too low,without affecting the voltage drop of the original LDO power tube.After reaching the overcurrent limit,the load current and power consumption drop ratio is positively correlated,the higher the load current,the more the overall power consumption drops than the original.As the load current increases,the power consumption drop ratio gradually increases from 0%to 20%~30%before the current foldback is triggered;after the current foldback starts,the power consumption drop ratio gradually increases from 20%~30%to 99%.When the load current does not reach the current foldback threshold,the LDO transient performance is not affected;when the load current reaches the current foldback threshold,the output voltage drops by approximately 500 mV,but the rest of the transient performance is not affected.
作者
李伙生
龙泳希
段志奎
于昕梅
LI Huosheng;LONG Yongxi;DUAN Zhikui;YU Xinmei(School of Electronic Information Engineering,Foshan University,Foshan 528225,China)
出处
《佛山科学技术学院学报（自然科学版）》
CAS
2024年第2期41-47,共7页
Journal of Foshan University(Natural Science Edition)
基金
广东普通高校重点实验室资助项目(2021KSYS008)。
关键词
低压差稳压器
过流保护
电流折返
精确采样
low drop-out regulator
over-current protection
foldback
precise sampling
