一种具有可调折返过流保护的LDO电路设计  

Design of an LDO Circuit with Adjustable Foldback Overcurrent Protection

作　　者：王晶[1] 张瑛[1] 李玉标 罗寅 方玉明[1] WANG Jing;ZHANG Ying;LI Yubiao;LUO Yin;FANG Yuming(School of Integrated Circuit Science and Engineering(Industry-Education Integration School),Nanjing University of Posts and Telecommunications,Nanjing 210023,China;Suzhou Convert Semiconductor Inc.,Suzhou 215600,China)

机构地区：[1]南京邮电大学集成电路科学与工程学院(产教融合学院),南京210023 [2]苏州锴威特半导体股份有限公司,江苏苏州215600

出　　处：《电子与封装》2025年第2期62-67,共6页Electronics & Packaging

基　　金：江苏省研究生科研与实践创新计划(KYCX24_1167);航空科学基金(202200240X9001)。

摘　　要：基于CSMC 0.18μm BCD工艺,设计了一种具有可调折返限流功能且无须内部补偿的低压差线性稳压器(LDO)。为防止闩锁,设计了一个可通过外部单电阻调整折返点的限流结构。此外,为了降低LDO环路补偿的设计难度,设计了一种无须内部补偿的LDO环路。该设计的限流点为13.78 mA,短路电流为0.56 mA,在输入电压为3.4~42 V、输出电压为3V时,线性调整率不超过0.5 mV/V,且在轻载和重载情况下,相位裕度分别为89.7°和74.7°,1 kHz时电源抑制比为-65 dB。Based on the CSMC 0.18μm BCD process,a low-dropout linear regulator(LDO)with adjustable foldback current limiting and no internal compensation is designed.To prevent latch-up,a current-limiting structure is implemented,which is adjustable via an external single resistor.Additionally,to reduce the design difficulty of LDO loop compensation,an LDO loop that requires no internal compensation is proposed.The current-limiting point of this design is 13.78 mA,with a short-circuit current of 0.56 mA.At an input voltage from 3.4 V to 42 V and an output voltage of 3 V,the linear adjustment rate does not exceed 0.5 mV/V.Under light and heavy load conditions,the phase margins are 89.7°and 74.7°,respectively,and the power supply rejection ratio at 1 kHz is-65 dB.

关 键 词：低压差线性稳压器 过流保护 折返限流 闩锁 无内部补偿 

分 类 号：TN433[电子电信—微电子学与固体电子学]