A common-mode choke coil includes a core having a winding core portion, a first winding and a second winding. A winding start side region ranges from one end portion to a position where a first winding is brought into contact with the winding core portion, and a winding finish side region ranges from the other end portion to a position where a second winding is brought into contact with the winding core portion. The first winding is wound on the winding core portion such that the first winding is positioned on a negative direction side in an x axis direction with respect to the second winding at the same turn in the winding start side region and the second winding is interposed between the first winding and the winding core portion in the winding finish side region.

A common-mode choke coil includes a core having a winding core portion, a first winding and a second winding. A winding start side region ranges from one end portion to a position where a first winding is brought into contact with the winding core portion, and a winding finish side region ranges from the other end portion to a position where a second winding is brought into contact with the winding core portion. The first winding is wound on the winding core portion such that the first winding is positioned on a negative direction side in an x axis direction with respect to the second winding at the same turn in the winding start side region and the second winding is interposed between the first winding and the winding core portion in the winding finish side region.

Disclosed herein is a pulse transformer that includes: a drum core including a winding core part and first and second flange parts provided at both ends of the winding core part in an axial direction; a plurality of wires wound around the winding core part; and a plate-like core fixed to the drum core so as to face a first surface of the first flange part that is parallel to the axial direction and a second surface of the second flange part that is parallel to the axial direction. A value of S1/S2 is 0.19 or more and 0.47 or less, where an area of the cross section of the winding core part that is perpendicular to the axial direction is S1 and a facing area between the plate-like core and the first or second surface is S2.

Disclosed herein is a pulse transformer that includes: a drum core including a winding core part and first and second flange parts provided at both ends of the winding core part in an axial direction; a plurality of wires wound around the winding core part; and a plate-like core fixed to the drum core so as to face a first surface of the first flange part that is parallel to the axial direction and a second surface of the second flange part that is parallel to the axial direction. A value of S1/S2 is 0.19 or more and 0.47 or less, where an area of the cross section of the winding core part that is perpendicular to the axial direction is S1 and a facing area between the plate-like core and the first or second surface is S2.

Disclosed herein is a coil component that includes a core, first to fourth terminal electrodes provided on a first flange part, fifth to eighth terminal electrodes provided on a second flange part, first and second wires bifilar wound around a winding core part, and third and fourth wires bifilar wound around the winding core part. One and other ends of the first to eighth wires are connected corresponding one of the first to eighth terminal electrodes. The first and second wires cross each other in a first crossing area. The third and fourth wires cross each other in a second crossing area different from the first crossing area.

The present invention provides a coil device which includes two coil elements in the same device and achieves an improved wire occupancy. The coil device includes a core including a winding core, and a winding wire part of which a first wire and a second wire are wound in a plurality of layers around the winding core, wherein the winding wire part includes a first part in which the first wire and the second wire of a same turn are wound adjacent to each other on a same layer, and a second part in which the first wire and the second wire of a same turn are wound in different layers without being adjacent to each other.

A common-mode choke coil includes a core having a winding core portion, a first winding and a second winding. A winding start side region ranges from one end portion to a position where a first winding is brought into contact with the winding core portion, and a winding finish side region ranges from the other end portion to a position where a second winding is brought into contact with the winding core portion. The first winding is wound on the winding core portion such that the first winding is positioned on a negative direction side in an x axis direction with respect to the second winding at the same turn in the winding start side region and the second winding is interposed between the first winding and the winding core portion in the winding finish side region.

A common-mode choke coil includes a core having a winding core portion, a first winding and a second winding. A winding start side region ranges from one end portion to a position where a first winding is brought into contact with the winding core portion, and a winding finish side region ranges from the other end portion to a position where a second winding is brought into contact with the winding core portion. The first winding is wound on the winding core portion such that the first winding is positioned on a negative direction side in an x axis direction with respect to the second winding at the same turn in the winding start side region and the second winding is interposed between the first winding and the winding core portion in the winding finish side region.

A coil device includes a winding core, a flange, and a terminal fitting. The winding core is wound by a wire. The flange is formed at an end of the winding core in its axial direction. The terminal fitting is attached to the flange. The terminal fitting includes an engagement part engaged with a circumferential wall part of the flange.

A coil device includes a winding core, a flange, and a terminal fitting. The winding core is wound by a wire. The flange is formed at an end of the winding core in its axial direction. The terminal fitting is attached to the flange. The terminal fitting includes an engagement part engaged with a circumferential wall part of the flange.