Evaluating the Influence of PMUT Mechanical Support Properties on Power Conversion Efficiency in Ultrasonically Powered Implants

Alessandro S. Savoia*, Domenico Giustiniano, Carlo Prelini, Marta Saccher, Amin Rashidi, Alberto Leotti, Vasiliki Giagka, Marco Ferrera

*Corresponding author for this work

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


Micromachined Ultrasonic Transducers (MUTs) are being explored as power converters in wirelessly powered biomedical implants. This paper investigates the role of mechanical support properties in piezoelectric MUTs (PMUTs) on their power conversion efficiency. For this purpose, a finite element model (FEM) of a PMUT array was developed and integrated with an equivalent circuit model (ECM). The study considered different mechanical support scenarios, from rigidly clamped to completely free. These were numerically analyzed and validated by impedance measurements and acoustic power transfer experiments on PMUT prototypes. The results show that reducing the mass of the mechanical support increases the Q factor, leading to a significant improvement in power conversion efficiency, with an efficiency increase factor of 5.6x from the clamped to the free case. This approach can potentially enhance overall power conversion efficiency, reduce the need for matching networks, and enable miniaturization in ultrasonically powered implants.
Original languageEnglish
Title of host publicationProceedings of the 2023 IEEE International Ultrasonics Symposium (IUS)
Place of PublicationPiscataway
Number of pages4
ISBN (Electronic)979-8-3503-4645-9
ISBN (Print)979-8-3503-4646-6
Publication statusPublished - 2023
Event2023 IEEE International Ultrasonics Symposium (IUS) - Montreal, Canada
Duration: 3 Sep 20238 Sep 2023


Conference2023 IEEE International Ultrasonics Symposium (IUS)
Abbreviated titleIUS 2023

Bibliographical note

Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care
Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.


  • PMUT
  • Ultrasonic MEMS
  • PZT
  • Ultrasonic Powering
  • Biomedical Implants
  • Power Transfer

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