초록 ▼

An electromagnetic interference (EMI) filter capacitor assembly is provided for shielding and decoupling a conductive terminal pin or lead of the type used, for example, in an implantable medical device against passage of external interference signals. The EMI filter is constructed of relatively ine

An electromagnetic interference (EMI) filter capacitor assembly is provided for shielding and decoupling a conductive terminal pin or lead of the type used, for example, in an implantable medical device against passage of external interference signals. The EMI filter is constructed of relatively inexpensive ceramic chip capacitors which replace relatively expensive feedthrough capacitors as found in the prior art. The chip capacitors are mounted directly onto a hermetic feedthrough terminal in groups of two or more which vary in physical size, dielectric material and capacitance value so that they self-resonate at different frequencies. This "staggering" of resonant frequencies and direct installation at the hermetic terminal provides the EMI filter with sufficient broadband frequency attenuation. In one preferred form, multiple chip capacitor groupings are mounted onto a common base structure, with each capacitor grouping associated with a respective terminal pin. In another preferred form, a non-conductive substrate is provided with metalized circuit traces to better accommodate the mounting of the chip capacitors. Additionally, novel chip capacitor geometry/termination-metallization is provided which significantly reduces the internal inductance of the capacitor to improve its high frequency performance as an EMI filter. Such reduced inductance chip capacitor designs are readily adaptable to incorporate multiple electrically isolated active plate sets within a single monolithic casing.

대표청구항 ▼

[ We claim:] [1.] A reduced inductance chip capacitor, comprising:a casing of dielectric material, the casing having first and second electrode plate means encased therein;first conductive termination surface means on a side of the casing and conductively coupled to the first electrode plate means;

[ We claim:] [1.] A reduced inductance chip capacitor, comprising:a casing of dielectric material, the casing having first and second electrode plate means encased therein;first conductive termination surface means on a side of the casing and conductively coupled to the first electrode plate means; andsecond conductive termination surface means on at least remaining sides of the casing relative to the first conductive termination surface means, and conductively coupled to the second electrode plate means.