Design of a fast-transient and high-stabilized GPS low dropout regulator

摘要

A high stabilized low dropout(LDO) voltage regulator fabricated for GPS radio frequency(RF) chip in SMIC 0.18μm CMOS technology is presented.The LDO mainly consists of bandgap reference,error amplifier,resistive feedback network and AC current path.A fast current path is added to improve the performance of LDO's transient response.Equivalent series resistance(ESR)compensation and internal Miller compensation are used to constitute the frequency compensation.The measurement results of the transient response of the output voltage show that it can recover within 2μs with less than 120 mV ripple when the load current is changed from 0 to 100 mA.The total quiescent current of LDO and bandgap reference(without load) is 260 μA.