Patent ID: 6745077
Filing Date: 2004-06-01
Classification: A61N

Abstract:
An implantable medical device adapted to receive power through an inductive link, said implantable medical device comprising:an implantable coil adapted to receive an inductively coupled signal from a power source; a rectifier circuit connected to the implantable coil, wherein the rectifier circuit rectifies the inductively coupled signal and produces an operating dc voltage therefrom; electronic circuitry powered from said operating dc voltage that performs a specified function, said electronic circuitry requiring differing amounts of power as a function of how the electronic circuitry is configured; and impedance transforming circuitry connected to the rectifier circuit that monitors changes in the amount of power used by the electronic circuitry and effectuates changes in load impedance as seen by the rectifier circuit so that the load impedance as seen by the rectifier circuit remains approximately constant.