FEED-THROUGH CAPACITOR

• Main Authors: YAMAOKA OSAMU, NAKABAYASHI KAZUHIRO, KAKIO GENMEI
• Format: Patent
• Language: English
• Published: 11.06.1993
• Subjects: BASIC ELECTRIC ELEMENTS; CABLES; CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES ORLIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE; CONDUCTORS; ELECTRICITY; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING ORDIELECTRIC PROPERTIES

PURPOSE:To obtain a feed-through capacitor exhibiting excellent noise elimina tion effect in a wide frequency range. CONSTITUTION:A feed-through capacitor is formed by arranging a pair of capacitance electrodes on dielectric composed of strontium titanate based ceramic. The relative permitivity of dielectric of the capacitor is large as compared with that of a capacitor wherein conventional titanium oxide based ceramic is used, and the self-resonance frequency becomes low to be in the range from several MHz to several tens of MHz, so that the insertion loss in the above frequency range becomes large. Since the strontium titanate based ceramic is superior to the titanium oxide based ceramic concerning radio waves absorption characteristics, the insertion loss in the frequency range from several hundreds of MHz to several GHz becomes large. The insertion loss is proportional to the noise elimination capability of the lead-through capacitor, and the larger the insertion loss becomes the larger the noise elimination capacity becomes.