The impact of DC-bus impedance on the switching performance of low-voltage silicon power MOSFETs

Franz Vollmaier*, Thomas Rainer Langbauer, Klaus Krischan, Roberto Petrella

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Typical DC-bus stabilization for low-voltage power circuits consists primarily of ceramic capacitors due to the capacity density and low equivalent series resistance (ESR) resulting in low conduction losses. Particularly in hard-switching and hard-commutation operation, the low ESR and high equivalent series inductance (ESL) of the capacitors in the commutation path restrict the damping of the switch node voltage overshoot and introduce high-frequency ringing, reducing the voltage margin of the transistor. Therefore, this paper analyzes the impact of the DC-bus impedance and proposes a DC-bus snubber based on an RC network to form the DC-bus impedance’s characteristic, which minimizes the overshoot voltage. A comprehensive simulation using measurement-derived component models is shown, which is verified by an in-situ measurement on a test PCB. Furthermore, transient measurements using a double pulse test setup show the effectiveness of the proposed approach.
Translated title of the contributionEinfluss der Zwischenkreisimpedanz auf das Schaltverhalten von LV-Silizium-basierten MOSFETs
Original languageEnglish
Pages (from-to)82–94
Number of pages13
JournalElektrotechnik und Informationstechnik
Volume140
Issue number1
DOIs
Publication statusPublished - Feb 2023

Keywords

  • Synchronous buck converter
  • DC-bus impedance
  • MOSFET switching performance
  • DC- bus snubber
  • Overvoltage damping
  • Voltage margin

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

Fields of Expertise

  • Sustainable Systems

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