A Switched Capacitor DC-DC Buck Converter for a Wide Input Voltage Range

Research output: Chapter in Book/Conference proceedings/Edited volumeConference contributionScientificpeer-review

1 Citation (Scopus)
10 Downloads (Pure)


In this paper, a power-efficient multiphase Recursive Switched Capacitor (RSC) converter is presented. Conventionally, RSC converters are used to obtain many different output voltages from a fixed input voltage. Here, the converter provides a fixed output voltage of 1 V at 1 mA from an input voltage ranging from 1.4 V to 4.5 V. It has one programmable stage (2:1 or 3:2) followed by four 2:1 stages. Contrary to most conventional topologies, depending on the input voltage, not all the stages are always deployed. This allows to increase the power efficiency of the whole architecture. The flying capacitance of the non-activated stages is transferred to the activated ones. Hence, for any given input voltage, 100 % of the on-chip capacitance is always used for the conversion. For a general 2:1 topology, an analytical analysis of the power losses is carried out and the impact of the overdrive voltage of the switches on the power efficiency is quantified.
A novel gate-driver technique for the switches involved in the conversion is proposed. It ensures an optimal overdrive voltage of the transistor, irrespective of its source and drain potentials. The 16-phase interleaved converter employs a charge recycling technique and uses a total on-chip capacitance of 3 nF.
The RSC converter is designed to be implemented in a standard 40 nm CMOS process which offers a capacitor density of approximately 2 nF/mm^2. Circuit simulations over the whole input voltage range show a power efficiency never lower than 54 % with a peak value of 92.7 %.
Original languageEnglish
Title of host publication2018 IEEE International Symposium on Circuits and Systems, ISCAS 2018
Subtitle of host publicationProceedings
Place of PublicationPiscataway, NJ
Number of pages5
ISBN (Electronic)978-1-5386-4881-0
ISBN (Print)978-1-5386-4882-7
Publication statusPublished - May 2018
EventISCAS 2018: IEEE International Symposium on Circuits and Systems - Florence, Italy
Duration: 27 May 201830 May 2018


ConferenceISCAS 2018
Abbreviated titleISCAS 2018
Internet address


  • DC-DC converter
  • switched-capacitor
  • voltage regulator
  • wide input voltage range

Fingerprint Dive into the research topics of 'A Switched Capacitor DC-DC Buck Converter for a Wide Input Voltage Range'. Together they form a unique fingerprint.

  • Cite this

    Urso, A., & Serdijn, W. A. (2018). A Switched Capacitor DC-DC Buck Converter for a Wide Input Voltage Range. In 2018 IEEE International Symposium on Circuits and Systems, ISCAS 2018: Proceedings (pp. 1-5). IEEE. https://doi.org/10.1109/ISCAS.2018.8351231