High PSR capacitor‐less LDO with adaptive bulk‐driven feedforward technique

Abstract This article presents a capacitor‐less low dropout (LDO) regulator with a high power supply rejection (PSR) for system‐on‐chip (SoC) applications. With the proposed adaptive bulk‐driven feedforward (ABDFF) technique, in which the ripples are injected adaptively to the bulk of power transistor, the LDO maintains a steady PSR enhancement in wide load conditions, and a lower quiescent current and faster load transient response are realized. Post‐layout simulation results show that the proposed LDO regulator achieves −75‐dB PSR at 1 MHz from 1 to 100 mA and 60‐fs figure of merit (FoM) with a 100‐pF load capacitor.