A fast-transient low-dropout regulator (LDO) with Super Class-AB OTA

Abstract

This paper presents a low power fast transient low-dropout regulator (LDO) employing a Super Class-AB operational transconductance amplifier (OTA). The proposed structure not only achieve large charging/discharging current at the gate of power transistor but also a gain factor, which not only shows excellent transient performance but also ensures enough line/load regulation. Without adding addition circuit structure, the proposed LDO demonstrates a comprehensive improvement, including enhanced line/load regulation and transient performance, when compared with conventional counterpart, implemented in 0.18 μm CMOS technology, the proposed LDO shows a transient voltage variation of 53 mV at Vout for a load step of 10 μA-200 mA and possesses a line/load regulation of 1.25 mV/V and 100 μV/mA respectively.