Donald K Haskell

US Patent:

6567259, May 20, 2003

Filed:

Sep 20, 2002

Appl. No.:

10/251672

Inventors:

Robert A. Stevenson - Canyon Country CA
Donald K. Haskell - Flagstaff AZ
John E. Roberts - Carson City NV

Assignee:

Greatbatch-Sierra, Inc. - Canyon Country CA

International Classification:

H01G 435

US Classification:

361302, 3613061, 361303

Abstract:

A feedthrough filter capacitor assembly for use in active implantable medical devices and a related process for manufacturing a monolithic ceramic capacitor utilizing dielectric materials having a dielectric constant greater than 7000, and preferably in the range of 8500 to 22,000. In the manufacture of the monolithic ceramic capacitor, one or more Curie point shifters and/or other dopants are added to the dielectric material to optimize the dielectric constant at the human body temperature of 37Â C. For manufacturing purposes, dopants may be added to the dielectric material to broaden the Curie point peak or point of maximum dielectric constant thereof. The effect is that when such capacitors and terminal assemblies are utilized in a high-voltage defibrillator circuit of an implantable medical device, the dielectric material is optimized so that during the delivery of high-voltage electrical energy, capacitance value of the capacitor drops substantially.