Monolithic LC feed-through filter having a ferrite body with a re-oxidized capacitive layer

摘要

This disclosure is directed to an improved LC filter which includes a cylindrical ferrite member of a semi-conductor material formed with an inner bore which axially extends through its central portion, and having its grain boundary and/or at least its outer peripheral surface formed into an insulating layer, an electrode provided at least on the outer peripheral surface of the cylindrical ferrite member, and a through-conductor inserted into the inner bore of the cylindrical ferrite member.