22 Scopus citations

Abstract

A fully integrated digital low-dropout regulator (DLDO) with a fast transient response, providing a regulated supply for system-on-chip (SoC) power management applications is proposed. Wideband operation and fast transient response are achieved through a transient enhanced proportional-integral controller, without compromising the stability of the DLDO at steady-state operation. The transient enhancement stage boosts loop-gain dynamically during load transients. In the gain boosting mode, the DLDO closed-loop bandwidth is increased, resulting in reduced undershoot/overshoot and fast settling. When the output voltage recovers to the desired level, the boost mode operation is disabled. For a load change with a 4-mA/ns slew rate between 10 and 50 mA, utilizing transient enhancement mode reduced the measured undershoot and overshoot by 35% and 17%, respectively. The characterization results show that the transient enhancement mode can reduce the settling time from 500 to 250 ns for a 10-50-mA load current change. The proposed DLDO operates with an input voltage ranging from 0.84 to 1.24 V, and output voltage ranging from 0.6 to 1 V. The maximum output current of the DLDO is 50 mA and the DLDO achieves a peak current efficiency of 99.2%, with DLDO figure of merit (FOM2) of 63.25 ps. The DLDO prototype chip is fabricated on a 0.13-μm CMOS technology and occupies a 0.0631-mm2 die area.

Original languageEnglish (US)
Article number7889005
Pages (from-to)2360-2370
Number of pages11
JournalIEEE Transactions on Very Large Scale Integration (VLSI) Systems
Volume25
Issue number8
DOIs
StatePublished - Aug 2017

Keywords

  • Digital control
  • digital low dropout regulator (DLDO)
  • fast transient
  • transient enhanced proportional-integral (PI) controller

ASJC Scopus subject areas

  • Software
  • Hardware and Architecture
  • Electrical and Electronic Engineering

Fingerprint

Dive into the research topics of 'A 50-mA 99.2% Peak Current Efficiency, 250-ns Settling Time Digital Low-Dropout Regulator with Transient Enhanced PI Controller'. Together they form a unique fingerprint.

Cite this