Inductive Signal Transfer in an Implantable Medical Device

• US 20140155685A1
• Filed: 11/30/2012
• Published: 06/05/2014
• Est. Priority Date: 11/30/2012
• Status: Active Grant

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Leigh, Charles Roger Aaron, Burch, Tony
• Granted Patent: US 9,821,155 B2
• Time in Patent Office: Days
• US Class Current: 600/25
• CPC Class Codes: A61N 1/0541 Cochlear electrodes
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: A61N 1/375 Constructional arrangements, e.g. casings

Abstract

An implantable medical device having a hermetically-sealed biocompatible housing configured to be implanted in a recipient. The implantable medical device includes at least one trans-housing transformer configured to transfer electrical signals through the housing.

Claims

1. An apparatus comprising:

a hermetically-sealed biocompatible housing configured to be implanted in a recipient; and

at least one trans-housing transformer configured to transfer electrical signals through the housing.

2. The apparatus of claim 1, wherein the at least one trans-housing transformer comprises:

a core entirely positioned in the housing and having first and second portions;

a plurality of secondary windings positioned within the housing around the second portion of the core; and

a plurality of primary windings positioned external to the housing and disposed around the first portion of the core such that varying current in the primary windings creates a varying magnetic flux in the core and a corresponding varying magnetic field through the secondary windings.

3. The apparatus of claim 2, wherein the core comprises a ferrite toroid core and wherein the housing comprises a main portion and an arcuate member extending from the main portion, wherein a first portion of the toroid core is disposed in the arcuate member such that the primary windings are disposed around an outer surface of the arcuate member and the secondary windings are disposed around a second portion of the toroid within the housing.

4. The apparatus of claim 2, wherein the core comprises an elongate ferrite core and wherein the housing comprises a main portion and a protrusion extending from the main portion, wherein the protrusion is configured to receive a first portion of the elongate core such that the primary windings are disposed around an outer surface of the protrusion and the secondary windings are disposed around a second portion of the elongate core within the housing.

5. The apparatus of claim 1, further comprising:

implant electronics positioned in the housing;

an implantable internal coil positioned external to the housing and electrically connected to a portion of the at least one trans-housing transformer external to the housing and configured to receive electrical signals transmitted by one or more devices positioned external to the recipient,

wherein the trans-housing transformer is configured to transfer electrical signals received by the internal coil to the implant electronics positioned in the housing.

6. The apparatus of claim 5, wherein the at least one trans-housing transformer comprises first and second trans-housing transformers, wherein the internal coil is electrically connected to the first trans-housing transformer and wherein the apparatus further comprises:

at least one functional component positioned external to the housing, and

wherein a portion of the second trans-housing transformer is electrically connected to the at least one functional component and is configured to transfer electrical signals generated by the implant electronics disposed in the housing to the at least one functional component.

7. The apparatus of claim 1, wherein the at least one trans-housing transformer comprises a plurality of trans-housing transformers configured to independently transfer separate electrical signals through the housing.

8. The apparatus of claim 1, further comprising:

at least one functional component positioned external to the housing; and

implant electronics disposed within the housing and configured to generate electrical signals for use by the at least one functional component,

wherein the at least one trans-housing transformer is configured to transfer the electrical signals generated by the implant electronics to the at least one functional component.

9. The apparatus of claim 8, wherein the at least one functional component is a component configured to at least one of electrically or mechanically stimulate the recipient.

10. A method comprising:

receiving one or more electrical signals at a trans-housing transformer partially disposed in a hermetically-sealed biocompatible housing configured to be implanted in a recipient; and

transferring, via the trans-housing transformer, the one or more electrical signals through the housing.

11. The method of claim 10, wherein the trans-housing transformer comprises a core entirely disposed in the housing and having first and second portions, a plurality of secondary windings positioned within the housing and disposed around the second portion of the core, and a plurality of primary windings positioned external to the housing and disposed around the first portion of the core, the method further comprising:

receiving the one or more electrical signals at the primary windings to induce a varying current in the primary windings that creates a varying magnetic flux in the core and a corresponding varying magnetic field through the secondary windings.

12. The method of claim 10, further comprising:

receiving the one or more electrical signals at an internal coil configured to be implanted in the recipient;

providing the one or more electrical signals to the trans-housing transformer; and

transferring, via the trans-housing transformer, the one or more electrical signals through the housing to implant electronics positioned in the housing.

13. The method of claim 10, further comprising:

generating the one or more electrical signals at implant electronics positioned in the housing;

providing the one or more electrical signals to the trans-housing transformer; and

transferring, via the trans-housing transformer, the one or more electrical signals through the housing to an internal coil positioned external to the housing.

14. The method of claim 10, further comprising:

generating the one or more electrical signals at implant electronics positioned in the housing;

providing the one or more electrical signals to the trans-housing transformer; and

transferring, via the trans-housing transformer, the one or more electrical signals through the housing to one or more functional components positioned external to the housing.

15. The method of claim 10, further comprising:

generating the one or more electrical signals at one or more functional components positioned external to the housing;

providing the one or more electrical signals to the trans-housing transformer; and

transferring, via the trans-housing transformer, the one or more electrical signals through the housing to implant electronics positioned in the housing.

16. An implantable medical device comprising:

an external coil configured to be worn by a recipient;

a hermetically-sealed biocompatible housing configured to be implanted in a recipient;

implant electronics positioned in the housing;

an implantable internal coil positioned external to the housing and configured to receive electrical signals transmitted by the external coil; and

at least one trans-housing transformer configured to transfer the electrical signals received at the internal coil through the housing to the implant electronics.

17. The implantable medical device of claim 16, wherein the at least one trans-housing transformer comprises:

a core entirely positioned in the housing and having first and second portions;

a plurality of secondary windings positioned within the housing around the second portion of the core; and

a plurality of primary windings positioned external to the housing and disposed around the first portion of the core such that varying current in the primary windings creates a varying magnetic flux in the core and a corresponding varying magnetic field through the secondary windings.

18. The implantable medical device of claim 17, wherein the core comprises a ferrite toroid core and wherein the housing comprises a main portion and an arcuate member extending from the main portion, wherein a first portion of the toroid core is disposed in the arcuate member such that the primary windings are disposed around an outer surface of the arcuate member and the secondary windings are disposed around a second portion of the toroid within the housing.

19. The implantable medical device of claim 17, wherein the core comprises an elongate ferrite core and wherein the housing comprises a main portion and a protrusion extending from the main portion, wherein the protrusion is configured to receive a first portion of the elongate core such that the primary windings are disposed around an outer surface of the protrusion and the secondary windings are disposed around a second portion of the elongate core within the housing.

20. The implantable medical device of claim 16, wherein the at least one trans-housing transformer comprises first and second trans-housing transformers, wherein the internal coil is electrically connected to the first trans-housing transformer and wherein the apparatus further comprises:

at least one functional component positioned external to the housing, and

wherein a portion of the second trans-housing transformer is electrically connected to the at least one functional component and is configured to transfer electrical signals generated by the implant electronics disposed in the housing to the at least one functional component.