Filtered feedthrough assembly for implantable medical device

• US 5,836,992 A
• Filed: 09/18/1997
• Issued: 11/17/1998
• Est. Priority Date: 10/04/1994
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Seifried, Lynn M., Thompson, David L., Sawchuk, Robert T.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US08/932,973
• Time in Patent Office: 425 Days
• Field of Search: 607/2, 607/36
• 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 filtered feedthrough assembly for an implantable medical device, the feedthrough assembly having internal and external portions, the internal portion being configured to be disposed inside a case of the implantable medical device, the external portion being configured to be disposed outside the case, the assembly comprising:

(a) an electrically conductive ferrule having opposing first and second ends and a centrally disposed opening extending between the first and second ends;

(b) an electrically conductive pin having first and second ends, the pin being disposed within and extending through the opening, the first end of the pin forming part of the internal portion, the second end of the pin forming part of the internal portion;

(c) an electrical insulator disposed between the ferrule and the pin, and

(d) a chip capacitor having first and second electrical contacts, the chip capacitor being mounted on the external portion, the first contact being connected electrically to the second end of the pin, the second contact being connected electrically to the second end of the ferrule.

2. The filtered feedthrough assembly of claim 1, wherein the first and second electrical contacts of the chip capacitor are attached, respectively, to the second end of the pin and the second end of the ferrule by a conductive epoxy adhesive.

3. A multi-lead filtered feedthrough assembly or an implantable medical device, the feedthrough assembly comprising a plurality of discrete feedthrough assemblies, the multi-lead feedthrough assembly having internal and external portions, the internal portion being configured to be disposed inside a case of the implantable medical device, the external portion being configured to e disposed outside the case, the multi-lead feedthrough assembly comprising a plurality of corresponding sets of electrically conductive ferrules, electrically conductive pins, electrical insulators and chip capacitors, each set comprising:

(i) a ferrule having opposing first and second ends and a centrally disposed opening extending between the first and second ends;

(ii) a pin having first and second ends, the pin being disposed within and extending through the opening of the ferrule, the first end of the pin forming part of the internal portion, the second end of the pin forming part of the internal portion;

(iii) an electrical insulator disposed between the ferrule and the pin, and

(iv) a chip capacitor having first and second electrical contacts, the chip capacitor being mounted on the external portion, the first contact being connected electrically to the second end of the pin, the second contact being connected electrically to the second end of the ferrule.