A 95.4% Hybrid Always-Dual-Path Recursive Step-Down Converter Using Adaptive Switching Level Control With 288 mΩ Large-DCR Inductor

Woojoong Jung, Minsu Kim, Hyunjun Park, Sung Min Yoo, Jun Hyeok Yang, Michael Choi, Jongshin Shin, Hyung Min Lee

Research output: Contribution to journalArticlepeer-review

Abstract

This article proposes a hybrid always-dual-path recursive (ADPR) step-down converter to achieve high efficiency using a small-volume inductor with large dc resistance (DCR). The ADPR step-down converter utilizes only low-voltage transistors (1.5 or 3.3 V) for power switches. The converter has adopted adaptive switching level control, which includes adaptive mode transition (AMT) and adaptive duty modulation (ADM), based on one dual-flipped saw-tooth waveform. AMT and ADM enable a wide range operation and ensure flying capacitor charge balance while leading to higher efficiency. In addition, a complementary switch guarantees the reliable operation at lower input voltage to 2.8 V. The 130-nm prototype converter used a small-volume 4.7 μH inductor with 288 mΩ DCR, a 10 μF output capacitor, and two 4.7 μF flying capacitors to verify highly efficient always-dual-path recursive operation. The measurement results show that the ADPR step-down converter can be suitable for converting Li-ion battery (2.8-4.2 V) to 0.7-1.1 V while the ratio of the inductor current over the load current (ILOAD) can be set between 0.42 and 0.66 at all range. The peak efficiency was measured up to 95.4% at VIN = 3.7 V and ILOAD = 75 mA. When VOUT = 1 V and ILOAD = 100 mA, the efficiencies were higher than 92.9% at whole input voltage ranges, ensuring small efficiency variation of 1.6%.

Original languageEnglish
Pages (from-to)2258-2269
Number of pages12
JournalIEEE Transactions on Power Electronics
Volume39
Issue number2
DOIs
Publication statusPublished - 2024 Feb 1

Bibliographical note

Publisher Copyright:
© 1986-2012 IEEE.

Keywords

  • Always-dual-path recursive
  • buck converter
  • hybrid multilevel converter
  • large dc resistance (DCR) inductor
  • stacked power stage

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

Fingerprint

Dive into the research topics of 'A 95.4% Hybrid Always-Dual-Path Recursive Step-Down Converter Using Adaptive Switching Level Control With 288 mΩ Large-DCR Inductor'. Together they form a unique fingerprint.

Cite this