一种快速瞬态响应无输出电容LDO的研究与设计  

Design of a Capacitor-less LDO with Improved Transient Response

作　　者：王程左 刘阳[1] 李威[1] 

机构地区：[1]电子科技大学电子薄膜与集成器件国家重点实验室,四川成都610054

出　　处：《微电子学与计算机》2015年第4期138-141,共4页Microelectronics & Computer

摘　　要：设计了一种基于自适应偏置放大器的具有快速瞬态响应的无输出电容LDO.自适应偏置放大器在发生负载瞬态响应时能够调节自身偏置电流以提供较大的输出电流来增加摆率;瞬态响应提升电路通过减小负载电容充放电电流而减小了输出电压的建立时间;通过并联反馈补偿来提高环路的稳定性.仿真结果表明,所设计的无输出电容LDO最大输出电流200mA,最小跌落电压200mV,静态电流仅16μA,全负载正负阶跃变化响应时间分别为2.5μs和3.5μs.This paper presents a capacitor-less LDO with improved transient response based on an adaptive biasing amplifier.The amplifier can adapta its bias aurent to be able to provide large output current to enhance the slew-rate when the load transient response occurs.By reduce the charging or discharging current of load capacitor,the transient response enhance circuit can decrease the built-up time of the output voltage.The proposed circuit has good loop stability with parallel feedback compensation.The results of simulation show that maximum of the output current is 200 mA,minimum of the dropout voltage is 200 mV,the quiescent current is only 16μA,the response time of a load current variation from 1 mA to 200 mA is 2.5μs and the response time of a load current variation from 200 mA to 1mA is 3.5μs.

关 键 词：无输出电容LDO 瞬态响应 并联反馈补偿 自偏置放大器 

分 类 号：TM44[电气工程—电器]