Fringe-field non-overlapping-electrodes discoidal feed-through ceramic filter capacitor with high breakdown voltage

Abstract

The size and placement of internal metallization areas as do collectively form each of two electrodes is improved in a typically discoidal feed-through ceramic filter capacitor having (i) multiple ceramic layers, (ii) a hole passing a wire that carries electrical signals which are to be filtered, (iii) metal lining the hole so as to make electrical contact with the wire, and (iv) an exterior metal band connected to ground. First internal metallization areas, each in the shape of a relatively smaller small-aperture disk, are centered about the body's hole in contact with the metal lining, each area being upon one of the body's multiple ceramic layers, the areas collectively serving as a first electrode of the capacitor. Second internal metallization areas, each in the shape of a relatively larger large-apertured disk also centered about the hole and upon one of the ceramic layers, make at their exterior edge surface electrical contact with the metal band, thereby to serve as a second electrode of the capacitor. The respective metallization areas of each electrode are both (i) spaced far apart by previous standards, and, preferably, (ii) are located upon alternating ceramic layers, making that any voltage breakdown path is necessarily both (i) long and with (ii) both radial and longitudinal components. According to this long path, the breakdown voltage is high, typically 3000-4000 volts, making the capacitor suitable for, inter alia, implanted cardiac defibrillators.