Tutorial: Data and Power Telemetry for Implants

Power and data telemetry are mandatory components for all implantable systems. Especially multichannel recorders and stimulators require both large power and high data rates. Nonetheless, in many systems the telemetry is just implemented with a holistic approach, but not analyzed in large detail. Based on the fact that most implantable devices dissipate the largest amount of power in the telemetry subsystem, a careful design or even active adaptability of the link are thought necessary in order to provide high energy-efficiency as well as to meet with regulatory compliance. Still today, most systems use RF data telemetry and suffer from large power consumption. Power delivery is mostly done without feedback control, or batteries are employed. On the emerging side, power efficient data transfer using UWB or non-RF telemetry, such as optical or ultrasonic approaches have shown to be excellent alternatives. Feedback controlled power telemetry or energy harvesting systems have shown high efficiency. This tutorial will give an overview and design guidelines for high-efficiency data and power telemetry for implantable systems. It first reviews the common RF based approaches, and secondly highlights new approaches such as energy harvesting and non-RF communication.