Multisite Bio-stimulating Implants Magnetoelectrically Powered and Individually programmed by a single transmitter
Abstract
Summary form only given. Implantable bioelectronics for electrically modulating activities of specific cells have shown great success and exciting potential in treating a wide range of diseases. Some of the most representative therapies are cardiac pacemakers and neuromodulators for motor function restoration, pain relief and neural disorder treatment. While several wireless miniaturized bio-stimulators have been demonstrated, most of them lack the capability of coordinated multisite stimulation, which is shown to be more effective in many scenarios. Equipping an implant with electrode/LED arrays is a straightforward approach to add extra stimulation channels, but the deployment flexibility of stimulating spots is limited due to leads. shows a wired retinal stimulator array to scale up the driving capability and ensure synchronization, but the heavy use of leads severely limits its applications. A two-site heart pacing system is proposed with two independently powered and controlled implants for flexible leadless deployment. Because the implants are inductively powered by two transmitters (TXs) with frequency multiplexing, they face stricter EM exposure constrains for power transmission, more challenging device synchronization, and limited scalability to more implants. To circumvent these problems, this paper presents a hardware platform for coordinated and miniaturized multisite stimulating implants, wirelessly powered and controlled by a single TX. Magnetoelectric (ME) wireless power transfer with high power and efficiency, low body absorption, and less sensitivity to misalignment, is co-designed with a robust SoC to enable reliable operation and individual programmability of the implants. The presented system features: (1) robust operation with 2V source amplitude variations, covering up to 40mm distance between TX and implants; (2) individual addressability and programmability of each implant, leveraging PUF IDs; (3) textgreater90% chip efficiency for 1.5-to-3.5V stimulation with fully programmable parameters; (4) no extra TX output power required for additional implants; (5) miniaturized implants with 6.2mm3 volume and 30mg mass.
Zhanghao Yu
PhD 2023, now at Intel
Yan He
PhD 2023, now at Nvidia
