Filtered feedthrough assembly for implantable medical device

• US 5,735,884 A
• Filed: 10/04/1994
• Issued: 04/07/1998
• Est. Priority Date: 10/04/1994
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Sawchuk, Robert T., Seifried, Lynn M., Thompson, David L.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US08/317,512
• Time in Patent Office: 1,281 Days
• Field of Search: 607/1, 607/36, 607/37
• US Class Current: 607/36
• CPC Class Codes: A61N 1/3754 Feedthroughs

Abstract

A feedthrough configuration for a hermetically sealed implantable medical device which includes a metal case having an aperture and a feedthrough in the aperture which includes an electrically conductive pin, an insulating material supporting the pin, a block spaced from the case and in electrical continuity with the pin and a device for electrical protection connected to the block and to the case. The device for electrical protection preferably includes two zener diodes, a first diode connected at the block and a second diode connected to the case with an electrical conductor connecting the two diodes in a back-to-back configuration.

Claims

1. A feedthrough assembly disposed in an aperture of an hermetically sealed implantable medical device, the medical device comprising a metal case having an interior surface and an exterior surface, the aperture extending between the interior and exterior surfaces of the case, the feedthrough assembly comprising:

(1) an electrically conductive pin extending through the aperture such that the pin has a first end projecting from the exterior surface of the case and a second end projecting from the interior surface of the case;

(2) an insulating material supporting the pin within the aperture and in sealing engagement with the pin;

(3) an electrically conductive block spaced from the case and in electrical continuity with the pin; and

(4) an electrical protection device electrically connected at a first point to the block and electrically connected at a second point to the case.

2. The feedthrough assembly according to claim 1 wherein the block has a flat portion to which the electrical protection device is connected.

3. The feedthrough assembly according to claim 1 wherein the electrical protection device comprises a first zener diode connected to the block, a second zener diode connected to the case, and an electrical conductor connected to each of the first and second diodes such the diodes are arranged in a back-to-back configuration.

4. The feedthrough assembly according to claim 3, wherein the feedthrough assembly is a first feedthrough assembly and a second feedthrough assembly having a third diode mounted thereon is positioned adjacent to the first feedthrough assembly, the diodes of the first and second feedthrough assemblies being electrically connected to the second diode.

5. The feedthrough assembly according to claim 1 wherein the electrical protection device is a chip capacitor.

6. A feedthrough assembly disposed in an aperture of an hermetically sealed implantable medical device, the medical device comprising a metal case having an interior surface and an exterior surface, the aperture extending between the interior and exterior surfaces of the case, the feedthrough assembly comprising:

(1) an electrically conductive pin extending through the aperture such that the pin has a first end projecting from the exterior surface of the case and a second end projecting from the interior surface of the case;

(2) an insulating material supporting the pin within the aperture and in sealing engagement with the pin;

(3) an electrically conductive block spaced from the case and in electrical continuity with the pin, the block having a peripheral skirt portion;

(4) an electrically conductive ferrule mounted in the aperture and in electrical continuity with the case, the ferrule having a peripheral upstanding portion; and

(5) an electrical protection device electrically connected at a first point to the peripheral upstanding portion of the ferrule and electrically connected at a second point to the peripheral skirt portion of the block.

7. A feedthrough assembly disposed in a case aperture for an hermetically sealed implantable medical device, the device comprising a metal case having an interior surface and an exterior surface, the case aperture extending between the interior and exterior surfaces, the assembly comprising:

(1) an electrically conductive pin extending through the aperture such that the pin has a first end projecting from the exterior surface of the case and a second end projecting from the interior surface of the case;

(2) an insulating material supporting the pin within the aperture and in sealing engagement with the pin;

(3) a first zener diode mounted on the feedthrough assembly and in electrical continuity with the pin, a second zener diode mounted on and in electrical continuity with the case, and an electrical conductor connected to each of the first and second diodes such the diodes are arranged in a back-to-back configuration.

8. The feedthrough assembly according to claim 7 wherein the feedthrough assembly further comprises an electrically conductive block spaced from the case and in electrical continuity with the pin, the first diode being mounted on the block.

9. The feedthrough assembly according to claim 7 further comprising a chip capacitor electrically connected at a first point to the case and electrically connected at a second point to the pin.

10. The feedthrough assembly according to claim 7 wherein the feedthrough assembly is a first feedthrough assembly and a second feedthrough assembly having a third diode mounted thereon is positioned adjacent to the first feedthrough assembly, the diodes of the first and second feedthrough assemblies being electrically connected to the second case mounted diode.