US 11,704,996 B2
Adaptive varactor based flexible matching network to support multiple implant conditions
Ashutosh Mehra, Minneapolis, MN (US); and Trevor D. Webster, Washington, DC (US)
Assigned to Medtronic, Inc., Minneapolis, MN (US)
Filed by Medtronic, Inc., Minneapolis, MN (US)
Filed on Apr. 22, 2021, as Appl. No. 17/237,288.
Claims priority of provisional application 63/013,885, filed on Apr. 22, 2020.
Prior Publication US 2021/0335126 A1, Oct. 28, 2021
Int. Cl. G08C 17/02 (2006.01); H04B 1/3827 (2015.01)
CPC G08C 17/02 (2013.01) [H04B 1/385 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A tunable circuit for use in an implantable medical device, the tunable circuit comprising:
a current generator configured to produce an alternating electrical current containing a signal at or above 13 MHz suitable for electronic communications;
an antenna configured to receive the alternating electrical current and produce an alternating electromagnetic field representative of the signal and a level of ambient impedance;
a plurality of fixed impedances arranged between the antenna and the current generator; and
a variable impedance arranged in the same electrical circuit as the plurality of fixed impedances, the variable impedance capable of being operated to dynamically maintain a matching impedance based upon temporal changes in the level of ambient impedance, in combination with the plurality of fixed impedances,
wherein the level of ambient impedance varies based upon a detected impedance, a received signal strength indicator, or another physical parameter of a material surrounding the implantable medical device.