Cardiac defibrillator with multi-phase ferroelectric/antiferroelectric capacitor

US5728138A · kind A · utility

Assignee

• The Penn State Research Foundation · US

Inventors

• Joseph P. Dougherty · New York, US
• Kamau Wa Gachigi · Narita, JP
• Thomas R. Shrout · Laureldale, US
• Sei-Joo Jang · State College, US
• Clive A. Randall · State College, US
• Philip M. Pruna · Canandaigua, US

Key dates

• Filing date: Jul 31, 1996
• Grant date: Mar 17, 1998
• Expiry date: Jul 31, 2016

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61N1/3956
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

A cardiac defibrillator includes a multilayer capacitor with a plurality of conductive electrodes and interspersed dielectric layers, each dielectric layer composed of constituents which cause it to exhibit an antiferroelectric phase. The constituents of each dielectric layer are such as to cause each layer to exhibit plural ferroelectric phases. The defibrillator includes a charging circuit for applying to the capacitor an electric field across each dielectric layer which causes a transition thereof through the plural ferroelectric phases. PLZT is the preferred dielectric material, at constituent values which cause the material to lie within the antiferroelectric phase and to exhibit plural ferroelectric phases.