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Advanced Multiphasing: Pushing the Limits of Fully Integrated Switched-Capacitor Converters

  • Nicolas Butzen
  • Michiel Steyaert
Chapter

Abstract

In this chapter, the major driving factors behind fully integrated power converters are discussed. Three challenges are identified that limit the performance of the most promising candidate for full integration which are switched-capacitor converters. These challenges include the significant parasitic coupling to the substrate, the limited capacitance density available on-chip, and the fact that this type of converter inherently has a small efficient conversion ratio range. Advanced multiphasing is introduced as an extension on the popular multiphasing concept, where multiple out-of-phase cores interact with each other to alleviate these issues. Several example AM techniques are discussed that either improve the efficiency of existing SC converters, both at high- and low-power densities, or even enable a fundamentally new type of SC converter topology whose conversion ratio can be efficiently scaled. All techniques are verified with measurements, resulting in state-of-the-art performances and showing the great potential that AM has to push the boundaries of fully integrated power conversion.

Keywords

Switched-capacitor DC–DC conversion Full integration Adiabatic charging Advanced multiphasing 

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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Nicolas Butzen
    • 1
  • Michiel Steyaert
  1. 1.ESAT-MICAS KU LeuvenHeverleeBelgium

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