一种快速瞬态响应型自启动LDO的设计

Design of a Self Starting LDO with Fast Transient Response

设计了一款适用于高压电源芯片的无片外电容快速瞬态响应型自启动低压差线性稳压器（LDO）。该LDO与芯片内部基准电路形成自供电自偏置环路,节省了芯片面积,适用电压范围为3.6~16.0V,输出电压为5.10V,具有功耗低、带宽宽等特点。电路采用Hspice进行仿真验证,在典型工艺角下,负载电流经100mA/μs突变时,输出电压突变量最大为98mV;在两种极端工艺角下,输出电压突变量最大为111mV。环路特性仿真验证表明,该LDO带宽为3.6 MHz,3dB带宽为2.5 MHz,相位裕度约75°,片内补偿电容仅3pF。

A self starting low dropout regulator（LDO）with fast transient response and capacitor-less for high voltage power management chip was designed.The LDO constituted a self-power and self-bias loop with the reference circuit which had reduced the circuit scale.The LDO featured low power consumption and wide bandwidth.Its practical input voltage range was 3.6-16.0V,and the output voltage was 5.10 V.The LDO was simulated and verified with Hspice.The results showed that the maximum output voltage step was 98 mV at a load step of 100mA/μs under the typical process corner,and the maximum output voltage step was 111 mV under two extreme processe corners.The LDO loop simulation showed that the circuit had a loop bandwidth of 3.6MHz,a 3dB loop bandwidth of 2.5 MHz,and a phase margin of about 75°with an on-chip compensation capacitor of only 3pF.