TELEMETRY NOISE REDUCTION

• US 20110137379A1
• Filed: 02/16/2011
• Published: 06/09/2011
• Est. Priority Date: 09/21/2007
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Strom, James, Grevious, John J., Wosmek, Mark G.
• Granted Patent: US 8,494,648 B2
• Time in Patent Office: Days
• US Class Current: 607/60
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: H01Q 1/526 Electromagnetic shields
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making

Abstract

A device includes a housing and electronics disposed in the housing. A telemetry antenna is disposed in the housing and is operably coupled to the electronics. A shielding coil is disposed between the housing and the telemetry antenna. The shielding coil has a first end and a second end. The second end is electrically terminated in circuitry of the electronics.

Claims

1. An implantable medical device comprising:

a housing;

electronics disposed in the housing;

a telemetry coil antenna disposed in the housing and operably coupled to the electronics; and

a first shielding coil disposed between the housing and the telemetry antenna and having a first end and a second end, the second end being electrically terminated in circuitry of the electronics, wherein the first shielding coil comprises a wound wire having a plurality of turns.

2. The device of claim 1, wherein the housing comprises a metallic material.

3. The device of claim 1, wherein the housing is formed from titanium.

4. The device of claim 1, wherein the first shielding coil comprises a first turn wound in a first direction and a second turn wound in a direction substantially opposite the first direction.

5. The device of claim 1, wherein the telemetry coil antenna is formed from a wire having a gauge and wherein the first shielding coil wire has the same gauge as the telemetry coil antenna wire or has a finer gauge than the telemetry coil antenna wire.

6. The device of claim 1, wherein the wire of the first shielding coil is wound such that the coil comprises multiple layers.

7. The device of claim 6, wherein the telemetry coil antenna is formed from a wire having a gauge and wherein the first shielding coil wire has a finer gauge than the telemetry coil antenna wire.

8. The device of claim 1, further comprising an electrical signal generator operably coupled to the electronics.

9. The device of claim 8, wherein circuitry of the electrical signal generator is configured such that the housing serves as a return electrode.

10. The device of claim 1, further comprising a recharge coil operably coupled to the electronics.

11. The device of claim 10, wherein the telemetry coil antenna, the recharge coil, and the first shielding coil are terminated in a common ground of the electronics.

12. The device of claim 10, wherein the telemetry coil antenna is disposed between the recharge coil and the first shielding coil.

13. The device of claim 12, further comprising a second shielding coil electrically coupled to the first shielding coil, wherein the second shielding coil is disposed between the recharge coil and the telemetry antennal coil.

14. The device of claim 13, wherein the first and second shielding coils are formed from a single wire

15. The device of claim 1, wherein further comprising a second shielding coil electrically coupled to the first shielding coil, and wherein the telemetry antenna is disposed between the first and second shielding coils.

16. The device of claim 12, wherein the first shielding coil and the second shielding coil are wound in opposing directions.

17. The device of claim 12, wherein the first and second shielding coils are formed from a single wire, and wherein the first end of the second shielding coil is the second end of the first shielding coil.

18. The device of claim 1, wherein the telemetry antenna comprises first and second opposing major surfaces and first and second opposing edge surfaces, wherein the first shielding coil is disposed adjacent the first edge surface.

19. The device of claim 18, further comprising a conductive layer disposed between the first major surface of the telemetry antenna and the housing.

20. A method for shielding a telemetry coil antenna from a housing of an implantable medical device, the telemetry coil antenna being disposed within the housing, the method comprising:

disposing a shielding coil between the housing and the telemetry coil antenna; and

electrically terminating an end of the shielding coil in electronics of the device.