First and second coils have winding axes in a laminated direction of base material layers and are magnetically coupled to each other. First and second capacitors are positioned in the laminated direction on layers different from layers on which the first and second coils are provided. The first and second coils are connected so that the winding directions of the first and second coils are opposite. The second capacitor is connected in parallel to a series circuit of the first coil and the second coil. The first capacitor is connected between a position where the first coil is connected to the second coil and a reference potential electrode. Mutual inductance caused by coupling between the first and second coils and the first capacitor provides a first attenuation pole and a parallel connection circuit of the series circuit and the second capacitor provides a second attenuation pole.

Provided is a laminated device. The laminated device includes: a laminate body where a plurality of sheets are laminated; a plurality of noise filter parts provided in the laminate body and each having at least one coil pattern; and a plurality of external electrodes provided outside the laminate body and connected to the plurality of noise filter parts, respectively. At least one of the plurality of noise filter parts has the number of coil patterns different from that of the rest.

The present disclosure discloses a circuit protection device including a first magnetic layer in which a plurality of magnetic sheets are laminated and of which at least a portion of one surface is exposed, a second magnetic layer in which a plurality of magnetic sheets are laminated and of which at least a portion of one surface is exposed, and a nonmagnetic layer in which a plurality of nonmagnetic sheets are laminated and which is disposed between the first and second magnetic layers. A noise filter part including a plurality of coil patterns is disposed in the nonmagnetic layer.

A multilayer band pass filter includes first and second LC parallel resonators. The first and second LC parallel resonators include a first inductor and a second inductor, respectively. The first inductor includes a first line conductive pattern, a first via conductive pattern, and a second via conductive pattern. The first line conductive pattern extends in the X-axis direction on a first dielectric layer. The first via conductive pattern and second via conductive pattern extend from the first line conductive pattern toward a second dielectric layer. The second inductor includes a third via conductive pattern extending in the Z-axis direction.

A resonant element includes first, second, and third plane electrodes, a first via electrode defining a first inductor, a second inductor, and a third inductor. The first via electrode connects the first plane electrode and the second plane electrode, and each of the second inductor and the third inductor connects the first plane electrode and the third plane electrode. The third plane electrode defines a first capacitor together with the second plane electrode, the second inductor includes second via electrodes, and the third inductor includes third via electrodes. Each of the second via electrodes and the third via electrodes is a columnar conductor extending in the extending direction of the first via electrode.

Provided is a frequency multiplexer. The frequency multiplexer includes a stacked structure. The stacked structure includes at least one insulating layer and a plurality of metal layers arranged alternately along a stacked direction. The stacked structure forms at least one first inductive element and at least one capacitive element. At least two of the plurality of metal layers are provided with respective first patterned metal structures. The first patterned metal structures in the at least two of the plurality of metal layers are electrically connected to form a first multilayer planar spiral coil structure. The first multilayer planar spiral coil structure constitutes the first inductive element.

A self-contained radio-frequency device featuring multiple overlapping coupled coil inductors in a planar configuration with overlaps selected for desired coupling between different pairs of coils, wherein the electromagnetic energy of the coils arises substantially only from the coils themselves and affects only the coils themselves. Overlapping configurations provide a compact space-saving form-factor for such a device a variety of applications, including filters, baluns, transformers, matching networks, amplifier stages, distributed amplifiers, and frequency multipliers. Space-saving is achieved by overlapping the coils while controlling the mutual inductance. The planar arrangements are applicable to a variety of technologies, such as integrated circuits (IC, ASIC, RFIC), ceramic multilayer technologies such as low temperature co-fired ceramics (LTCC), and to printed circuit boards (PCB). Planar arrangements of overlapping coils is illustrated with respect to filters, tunable filters and Q-enhanced filters.

A circuit board includes a glass substrate having a first surface and a second surface facing away from the first surface; a first coil wiring pattern formed on the first surface and a second coil wiring pattern formed on the second surface, the first and second coil wiring patterns constituting part of a coil; a through hole extending through a predetermined portion of the glass substrate from an end of the first coil wiring pattern to an end of the second coil wiring pattern; a through hole inner conductive surface formed on the inner side of the through hole, the first and second coil wiring patterns and the through hole inner conductive surface constituting the coil wound around a direction perpendicular to an axis of the through hole and to a direction in which the first and second coil wiring patterns extend.

An improved filter for high frequency, such as 5G wireless communication, may include inductor-Q improvement and reduced die-size with a hybrid 3D-inductor integration. In some examples, the inductors may be formed using an IPD and a fan-out package. For instance, a first multilayer substrate comprises a plurality of metal insulator metal (MIM) capacitors formed using various layers (e.g., M1 and M2) and a first portion of the 3D inductors, and a second multilayer substrate comprises at least a second portion of the 3D inductors. The 3D inductors may be electrically coupled to the MIM capacitors to form at least one filter network.

A coil component includes a first coil and a second coil that are magnetically coupled to each other. The coil component includes a multilayer body, first wiring patterns, second wiring patterns, and third wiring patterns. The first coil includes a portion in which the first wiring patterns and the third wiring patterns are electrically connected to each other by a first via conductor and a second via conductor through the first wiring patterns and the third wiring pattern to connect the wiring patterns in parallel. The second coil includes a portion in which the second wiring patterns and the third wiring patterns are electrically connected to each other by a third via conductor and a fourth via conductor through the second wiring patterns and the third wiring pattern to connect the wiring patterns in parallel.