Implantable medical device charging apparatus having both parallel and series resonators
View Patent ↗An implantable medical device charging apparatus includes a charging circuit. The charging circuit includes a series resonator responsive to a signal applied to the charging circuit. During operation, the series resonator inductively couples to a secondary coil within an implantable medical device to transfer energy to the secondary coil. The charging circuit also includes a parallel resonator coupled to the series resonator. The parallel resonator filters a first component of the signal from propagating to the series resonator.
1. An implantable medical device charging apparatus comprising:
a charging circuit, wherein the charging circuit includes:
a series resonator responsive to a signal applied to the charging circuit, the series resonator configured to inductively couple to a secondary coil within an implantable medical device to transfer energy to the secondary coil, the signal having a first component having a first frequency within a first frequency band and a second component having a second frequency within a second frequency band; and
a first parallel resonator coupled to the series resonator, the first parallel resonator configured to filter the first component of the signal from propagating to the series resonator.
2. The implantable medical device charging apparatus of claim 1 , wherein the series resonator includes a primary coil and the first parallel resonator includes a parallel inductor.
3. The implantable medical device charging apparatus of claim 2 , wherein the primary coil is a radial inductor and wherein the parallel inductor is a torodial inductor.
4. The implantable medical device charging apparatus of claim 1 , wherein the charging circuit further comprises:
a signal generator configured to generate the signal, wherein the first component is switching noise caused by the signal generator.
5. The implantable medical device charging apparatus of claim 4 , wherein the first frequency band ranges from 50 megahertz (MHz) to 100 MHz.
6. The implantable medical device charging apparatus of claim 1 , wherein the first parallel resonator is configured to provide the second component of the signal to the series resonator, wherein the second frequency band has a lower frequency range than the first frequency band, wherein the series resonator resonates in response to receiving the second component of the signal.
7. The implantable medical device charging apparatus of claim 1 , wherein the charging circuit further comprises:
a signal generator configured to generate the signal, wherein the first component is a harmonic of the signal.
8. The implantable medical device charging apparatus of claim 7 , wherein the first frequency band ranges from 60 kilohertz (kHz) to 100 kHz.
9. The implantable medical device charging apparatus of claim 1 , wherein the second frequency band ranges from 9 kilohertz (kHz) to 11 kHz.
10. The implantable medical device charging apparatus of claim 1 , wherein the charging circuit further comprises:
a second parallel resonator coupled in series with the first parallel resonator and the series resonator, the second parallel resonator configured to filter a third component having a third frequency within a third frequency band of the signal from propagating to the series resonator.
11. The implantable medical device charging apparatus of claim 10 , wherein the first frequency band ranges from 60 kilohertz (kHz) to 100 kHz and the third frequency band ranges from 50 megahertz (MHz) to 100 MHz.
12. A method comprising:
generating a signal at an implantable medical device charging apparatus, wherein the signal has a first component having a first frequency within a first frequency band and has a second component having a second frequency within a second frequency band;
applying the signal to a charging circuit, wherein the charging circuit includes a series resonator and a first parallel resonator, wherein the first parallel resonator inhibits the first component of the signal from propagating to the series resonator and provides the second component of the signal to the series resonator, and wherein the second component of the signal causes a primary coil of the series resonator to inductively couple to a secondary coil of an implantable medical device.
13. The method of claim 12 , wherein the series resonator resonates in response to the second component of the signal.
14. The method of claim 12 , wherein the first parallel resonator resonates in response to the first component of the signal to inhibit the first component of the signal from propagating to the series resonator.
15. The method of claim 12 , wherein the first frequency band ranges from 60 kilohertz (kHz) to 100 kHz or from 50 megahertz (MHz) to 100 MHz, and wherein the second frequency band ranges from 9 kHz to 11 kHz.
16. The method of claim 12 , further comprising communicating data to a receiver within the implantable medical device, wherein the data is communicated over the first frequency band and wherein the implantable medical device charging apparatus charges the implantable medical device over the second frequency band.
17. The method of claim 12 , wherein the signal has a third component having a third frequency within a third frequency band, wherein the charging circuit includes a second parallel resonator, wherein the second parallel resonator inhibits the third component of the signal from propagating to the series resonator and provides the second component of the signal to the series resonator.
18. The method of claim 17 , wherein the first frequency band ranges from 60 kilohertz (kHz) to 100 kHz and the third frequency band ranges from 50 megahertz (MHz) to 100 MHz.
19. A circuit comprising:
a signal generator configured to generate a signal, the signal having a first component having a first frequency within a first frequency band and a second component having a second frequency within a second frequency band;
a parallel resonator coupled to the signal generator, wherein the parallel resonator includes a parallel inductor and a parallel capacitor;
a series resonator coupled to the parallel resonator, the series resonator configured to inductively transfer energy to a secondary coil within an implantable medical device, wherein the series resonator includes a capacitor and a primary coil, wherein the parallel resonator is configured to inhibit the first component from propagating to the series resonator and to provide the second component of the signal to the series resonator.
20. The circuit of claim 19 , wherein the first component is a harmonic of the signal or switching noise caused by the signal generator.