Patent ID: 8362742

Claim:
A passive recharging system for an implantable medical device comprising: a) a secondary coil associated with the implantable medical device; b) an external power source including: a primary coil; and a modulation circuit operatively coupled to said primary coil, said modulation circuit being capable of driving said primary coil at a carrier frequency when said primary coil is in proximity to said secondary coil and of varying the carrier frequency in response to sensor data received from the implantable medical device; c) a first sensor associated with the implantable medical device and in communication with the modulation circuit, the first sensor being capable of sensing a first condition indicating a need to adjust the carrier frequency during a charging process; d) a second sensor associated with the implantable medical device and in communication with the modulation circuit, the second sensor being capable of sensing a second condition which is affected by the carrier frequency.