An Output-Capacitorless Low-Dropout Regulator with Slew-Rate Enhancement

Abstract

A novel output-capacitorless low-dropout regulator (OCL-LDO) with an embedded slew-rate-enhancement (SRE) circuit is presented in this paper. The SRE circuit adopts a transient current-boost strategy to improve the slew rate at the gate of the power transistor when a large voltage spike at the output is detected. In addition, a feed-forward transconductance cell is introduced to form a push–pull output structure with the power transistor. The simulation results show that the maximum transient output voltage variation is (Formula presented.) when the load current (Formula presented.) is stepped from (Formula presented.) to (Formula presented.) in (Formula presented.) with a load capacitance of (Formula presented.), and the settling time is (Formula presented.). The proposed OCL-LDO consumes a quiescent current of (Formula presented.) and has a dropout voltage of (Formula presented.) for the maximum output current of (Formula presented.).