Packaging Methods for Magnetoelectric Transducers Used as Wireless Power Receivers

Magnetoelectric (ME) transducers, composed of piezoelectric and magnetostrictive layers, have recently been demonstrated as a receiver in wireless power transfer (WPT) to miniature implantable medical devices (IMDs). Due to their complex mechano-magnetic-electric interactions, methods for biocompatible coating and packaging of ME transducers within a small IMD need to be investigated to achieve optimal ME response. This paper describes the effects of biocompatible coating and packaging using Polydimethylsiloxane (PDMS) on ME response. Three bar-shaped ~ 5×1×1 mm
³
ME transducers were fabricated with a 508 µm thick piezoelectric layer. In air, adding ~ 35 µm of PDMS coating reduced the received power (P
L
) by 19.4% (131.04 µW vs. 105.62 µW). The ME transducer were mounted on a printed circuit board (PCB) and inside a custom 3D-printed holder. The PCB mounting had no significant effect on ME transducer P
L
, but the 3D-printed holder considerably reduced P
L
from 112.89 µW to 39.02 µW, when measured in a water medium.