Patent ID: 8668839

Claim:
A ferrite core, comprising: a Mn—Zn—Co ferrite comprising a basic component, subcomponents, and unavoidable impurities, wherein, as the sub-components, silicon oxide (in terms of SiO 2 ): 50 to 400 mass ppm, and calcium oxide (in terms of CaO): 1000 to 4000 mass ppm are added to the basic component consisting of iron oxide (in terms of Fe 2 O 3 ): 51.0 to 53.0 mol %, zinc oxide (in terms of ZnO): more than 12.0 mol % and 18.0 mol % or less, cobalt oxide (in terms of CoO): 0.04 to 0.60 mol %, and manganese oxide (in terms of MnO): balance; and amounts of phosphorus, boron, sulfur, and chlorine in the unavoidable impurities are reduced as follows phosphorus: less than 3 mass ppm, boron: less than 3 mass ppm, sulfur: less than 5 mass ppm, and chlorine: less than 10 mass ppm, wherein the ferrite core is composed of the Mn—Zn—Co ferrite in a compacted state, the ferrite core having an outer diameter of from about 2 mm to about 6 mm.