Patent ID: 7774069
Filing Date: 2010-08-10
Classification: A61M,A61N

Abstract:
1. A system for transcutaneous energy transfer, comprising: an implantable medical device having componentry for providing a therapeutic output, said implantable medical device having an internal power source and a secondary coil operatively coupled to said internal power source, said implantable medical device adapted to be implanted in a patient; an external power source having a primary coil, said external power source providing energy to said implantable medical device when said primary coil of said external power source is placed in proximity of said secondary coil of said implantable medical device and thereby generating a current through said internal power source; an alignment indicator, operatively coupled to said internal power source, measuring said current and reporting an alignment between said primary coil and said secondary coil based on said current; wherein said current is compared with a predetermined value associated with an expected alignment between said primary coil and said secondary coil; wherein said internal power source has an internal impedance and wherein said predetermined value is adjusted as a function of said internal impedance of said internal power source; wherein said internal impedance of said internal power source increases over time; and wherein said predetermined value decreases as said internal impedance increases.