ANCHOR LOSS IN MILLIMETER-SCALE ULTRASONIC WIRELESS IMPLANTABLE DEVICES

ANCHOR LOSS IN MILLIMETER-SCALE ULTRASONIC WIRELESS IMPLANTABLE DEVICES

Researchers at UC Berkeley have developed a method to enable efficient piezoelectric transducer-based ultrasonic power and data link for miniaturized implantable medical devices.

Acoustic links for implantable medical devices (implants) have gained attention primarily because they provide a route to wireless deep-tissue systems. Piezoelectric crystals serve as a critical component in the construction of ultrasonic wireless implantable devices, as these crystals convert acoustic mechanical energy into electrical energy by the piezoelectric effect. Implant miniaturization is a key research goal, as smaller implants result in less tissue damage. However, implant size in most acoustic systems is limited by the piezoelectric crystal used for power harvesting and data communication, and further miniaturization of the piezoelectric crystal can degrade system power transfer efficiency and data transfer reliability.

Stage of Research

The inventors have developed a new method for packaging implant piezoelectric crystals. Their method maximizes power transfer efficiency from the acoustic power at the piezo surface to the power delivered to the electrical load and information transfer across the acoustic link, providing a path towards the further miniaturization of ultrasonic implants. Their method relies on placing piezo-to-substrate anchors to the piezo regions where the vibrational displacement of the mode of interest is zero. The inventors validate their method and show that a strongly coupled, high quality piezo with properly located and sized anchors minimizes anchor loss in millimeter-scale ultrasonic wireless implants.

Applications

  • Method for packing the implant piezoelectric crystal that enables the design of efficient acoustic power and data link

Advantages

  • Reducing the anchor size decreases anchor loss and improves piezo quality factor
  • Improves system electromagnetic coupling, achieving higher power and data transfer efficiency

Stage of Development

Research – in vitro

Publications

Sonmezoglu S, Darvishian A, Shen K, Bustamante MJ, Kandala A, Maharbiz MM. A Method and Analysis to Enable Efficient Piezoelectric Transducer-Based Ultrasonic Power and Data Link for Miniaturized Implantable Medical Devices. IEEE Trans Ultrason Ferroelectr Freq Control. 2021. doi: 10.1109/TUFFC.2021.3093867

Related Web Links

https://maharbizgroup.wordpress.com/

Keywords

Anchor loss, piezoelectric crystal, acoustic link, ultrasonic implant

Reference

Chan Zuckerberg ref. CZB-149B, Berkeley ref. B20-092

Patent Information:
For Information, Contact:
Garima Syal
IP & Corporate Paralegal
CZ Biohub
ip@czbiohub.org
Inventors:
Michel Maharbiz
Soner Sonmezoglu
Keywords:
Acoustic Link
Anchor Loss
Piezoelectric Crystal
Ultrasonic Implant