Asymmetrical filter
AssigneeAVX Corporation
InventorsJoseph M. Hock, John L. Galvagni
Life of this patent
Estimating the term…
Abstract
Disclosed is methodology and apparatus for producing an asymmetrical filter for use with implantable medical devices, and in other input filtering environments. Differing forward and reverse characteristic responses are provided by inserting a low value resistor in series with heart connecting leads so that EMI input protection may be provided without significantly reducing energy transfer from the protected device. Improved protection against voltage transients is provided with present arrangements of differentiated series impedance. Higher frequency energy is allowed out of a subject device than is allowed into such device, which allows for attenuation of undesired frequency ranges entering the filter while allowing output pulses to exit without distortion.
Claims21
A filtered feedthrough capacitor arrangement for use in a patient-implantable medical environment, comprising:
- a feedthrough capacitor having a main body and at least a first lead emerging from one side of said main body and a second lead emerging from another side of said main body;
- a feedthrough filter associated with at least one of said feedthrough capacitor leads;
- and
- an asymmetrical filter, associated with said at least one of said feedthrough capacitor leads, and electrically situated between said feedthough capacitor and said feedthrough filter, said asymmetrical filter including a low value resistance for providing differing forward and reverse characteristic responses of the filtered feedthrough capacitor arrangement.
A filter circuit for use electrically interposed between a feedthrough capacitor and a feedthrough filter of the type having plural respective leads, and provided for use in association with implantable medical devices and other input and/or output filtering related environments, said filter circuit comprising:
- a resistor mounting substrate;
- and
- a plurality of predetermined small value resistors supported on said substrate and arranged for connection in series with input or output leads of a further device, collectively providing with an associated feedthrough capacitor and feedthrough filter an asymmetrical filtering arrangement capable of passing different energy levels in respective forward and reverse directions.
A method for improving EMI and voltage transient protection for implantable medical devices, including providing differing forward and reverse characteristic responses thereof by inserting a predetermined low value resistance in series with biocompatible connecting leads of the implantable device, so that EMI input protection may be provided thereto without significantly reducing energy transfer from the protected implantable device.
Dependencies are inferred from the claim text.