A low power consumer capacitor-less low dropout regulator with super class AB CMOS OTA

A low power consumer capacitor-less low dropout regulator (LDO) with supper class AB CMOS operational transconductance amplifier (OTA) has been proposed in this paper. The OTA of this design is based on the combination of class AB differential input stages and local common-mode feedback which provides additional common-mode sensing techniques thus to obtain a high common mode rejection ratio (CMRR). Local common-mode feedback (LCMFB) is applied to various class AB differential input stages, leading to different class AB OTA topologies. The presented LDO is fabricated in a 0.18 um standard CMOS process. The circuit consumes a quiescent current of 1.37 uA, regulating the output at 1.0 V with maximum output current of 600 mA from a voltage supply of 1.2V. It achieved full range stability from 1mA to 100 mA load current at a maximum 100pf load capacitor.