US 12,142,415 B2
Coil device
Kyosuke Inui, Tokyo (JP); Yuichi Oyanagi, Tokyo (JP); Toru Tonogai, Tokyo (JP); and Toshiyuki Anbo, Tokyo (JP)
Assigned to TDK CORPORATION, Tokyo (JP)
Filed by TDK CORPORATION, Tokyo (JP)
Filed on Oct. 28, 2021, as Appl. No. 17/512,790.
Claims priority of application No. 2020-185212 (JP), filed on Nov. 5, 2020.
Prior Publication US 2022/0139609 A1, May 5, 2022
Int. Cl. H01F 5/00 (2006.01); H01F 17/04 (2006.01); H01F 27/29 (2006.01)
CPC H01F 27/292 (2013.01) [H01F 17/04 (2013.01); H01F 2017/048 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A coil device comprising:
a core containing magnetic particles and a resin component;
a coil comprising a conductor having a coil shape; and
a terminal electrode formed on a part of an outer surface of the core and electrically connected to an end of the conductor drawn from the coil; wherein
the terminal electrode comprises a first electrode layer in contact with the end of the conductor and a second electrode layer located outside the first electrode layer,
both the first electrode layer and the second electrode layer include conductive powder and resin,
a content of the resin in the second electrode layer is higher than a content of the resin in the first electrode layer,
an average thickness of the second electrode layer is thicker than an average thickness of the first electrode layer, and
a non-overlapping part in which a part of the first electrode layer is not covered with the second electrode layer extends toward an end of the terminal electrode from a position which is away from a contact part of the conductor and the first electrode layer with a predetermined length, L1, in a first axis direction.