Taiyo Yuden Co., Ltd.

Takayuki Maruyama

Hideharu Suzuki

Yoshinari Nakada

Satoshi Kimura

Takahiro Samata

Koichi Iguchi

Koihci Iguchi

A wire wound electronic part includes a ferrite core comprising ferrite having a columnar wire wound core and flanges formed at both ends thereof, a coil conductor wound around the wire wound core of the ferrite core, and at least a pair of terminal electrodes having a Cu conduction layer disposed to the outer surface of the flange, in which both ends of the coil conductor wound around the wire wound core are conductively connected to the terminal electrodes. The terminal electrode is formed by coating an electrode paste containing a Cu powder and a glass frit to the outer surface of the ferrite core, and then applying a heat treatment to the ferrite core. There is a reaction layer of a portion of the ferrite core and the glass frit at a boundary between the ferrite core and the Cu conduction layer. The terminal electrodes has the peel strength identical with that of an existent Ag terminal electrode, without forming a plate layer.

Wire wound electronic part

A wire wound electronic part includes a core having a wire wound core and flanges formed on both ends thereof, a coil conductor wound around the wire wound core and terminal electrodes disposed at the bottom of the flange, in which both ends of the coil conductor are conductively connected to the terminal electrodes by a solder, wherein a pair of grooves are formed at the bottom crossing the wire wound core of one of the flanges. The groove has a bottom and side walls disposed being slanted on both sides thereof, in which the vertical height for the side wall is formed larger than the length for the bottom of the side wall. The terminal electrodes are contained in the groove, and edge portion in the lateral direction of the terminal electrode is restricted by the side wall of the groove. The edge portion in the lateral direction of the terminal electrode is restricted by the side wall of the groove, which makes the lateral size stable and suppresses the movement of the molten solder in the lateral direction of the groove, thereby preventing unstable height and attitude of the wire wound electronic part upon mounting to a circuit substrate.

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Gunma, Japan

Takayuki Maruyama