Telemetry for Implantable Medical Devices: Part 2 - Power Telemetry

This three-part article focuses on power and data telemetry for implantable medical devices (IMDs). It is not restricted to circuit and system descriptions but outlines the background of the application, along with typical requirements, to illuminate why the circuits are being built as described in state-of-the-art publications. In order to adequately cover this wide range of topics, the article has been split into three parts. In the first part, we reviewed tissue properties, regulations, standards, and safety limits for EM and optical telemetry and its application to the human body. This second part focuses on power telemetry, with an emphasis on the inductive link and the corresponding power management circuits, and gives a short overview of more recent advances such as energy harvesting for IMDs. The third and last part will be dedicated to data telemetry concepts for IMDs. These will be reviewed in principle, then split mostly into electromagnetic and optical approaches. To conclude, an example of a system realizing some of the aforementioned ideas will be provided.