A Modular Quad-mode Capacitor-Less Digital Low-Dropout Regulator

Digital low-dropout regulators (DLDOs) are widely used for power management in the system-on-chip (SoC) because of their low-voltage operation and process scalability. This work proposes a modular quad-mode DLDO, which can be easily and quickly modified for a wide variety of applications. Owed to its "brick-like"architecture, the proposed DLDO has four operating modes and can be easily changed into different loading specifications. Besides, the proposed DLDO can achieve a fast transient response without output capacitors. With these features, using the proposed DLDO can significantly shorten the R&D time of each project development. This work was fabricated in a 28-nm CMOS process, and post-layout simulation shows 99.78% peak current efficiency with only 220 μA quiescent current.