A filter element is mounted on a module substrate. The filter element includes a ground terminal and a pair of signal terminals. The module substrate includes a ground plane, a ground land, and an inductance adjusting line that connects the ground land to the ground plane. The ground terminal of the filter element is connected to the ground land of the module substrate. The inductance adjusting line includes an in-plane extending portion that extends in an in-plane direction of the module substrate.

Provided is a power converter in which a magnetic core of a noise filter can be prevented from magnetic saturation and the noise filter can be downsized. A noise filter 140 provided in a power converter includes: a magnetic core 1 formed with a single through-hole 1A and forming a closed magnetic circuit; first wiring 11 having one end 81 connected to a power conversion circuit and the other end drawn out from the second opening 3, and running through the through-hole 1A from one first opening 2 to the other second opening 3; second wiring 21 having one end connected to the other end of the first wiring 11 and the other end 82 drawn out from the first opening 2 as a filter output end, and running through the through-hole 1A from the second opening 3 to the first opening 2; a first capacitor 41 provided between the ground and a connecting portion 31 of the first wiring 11 and the second wiring 21; and the second capacitor 51 provided between the other end 82 of the second wiring 21 and the ground.

Provided is a power converter in which a magnetic core of a noise filter can be prevented from magnetic saturation and the noise filter can be downsized. A noise filter 140 provided in a power converter includes: a magnetic core 1 formed with a single through-hole 1A and forming a closed magnetic circuit; first wiring 11 having one end 81 connected to a power conversion circuit and the other end drawn out from the second opening 3, and running through the through-hole 1A from one first opening 2 to the other second opening 3; second wiring 21 having one end connected to the other end of the first wiring 11 and the other end 82 drawn out from the first opening 2 as a filter output end, and running through the through-hole 1A from the second opening 3 to the first opening 2; a first capacitor 41 provided between the ground and a connecting portion 31 of the first wiring 11 and the second wiring 21; and the second capacitor 51 provided between the other end 82 of the second wiring 21 and the ground.

A filter module includes a circuit board on or in which a ground electrode is provided, and a low pass filter on the circuit board. The low pass filter includes first and second inductors, and a capacitor. The first and second inductors are cumulatively connected to each other. Relationships of Lp+Lg−M≥0 and Lp−M<0 are satisfied, where Lp denotes an inductance of a path between a connection portion between the first and second inductors and a ground terminal, Lg denotes an inductance of a path between the ground terminal and the ground electrode, and M denotes a mutual inductance between the first and second inductors.

An electronic device includes an IC mounted on a substrate and a filter circuit connected to the IC. The filter circuit includes a coil component and a capacitor. The coil component includes a multilayer body, a first coil including a portion of multiple wiring patterns laminated in the multilayer body, a second coil provided on layers different from those of the first coil and including a portion of the multiple wiring patterns, and first, second and third electrodes provided on side surfaces. An opening of the first coil is at least partially overlapped with an opening of the second coil when viewed from a main surface direction. The third electrode is grounded via the capacitor. The first coil has an inductance lower than that of the second coil.

A filter device includes a dielectric substrate, first and second ground electrodes connected to a ground terminal, and resonators between the ground electrodes and electromagnetically coupled to each other. The ground electrodes are at different positions in a normal direction of the dielectric substrate. Each of the resonators includes a first capacitor electrode partially overlapping with the first ground electrode in plan view of the dielectric substrate, a second capacitor electrode partially overlapping with the second ground electrode in plan view of the dielectric substrate, and a via connecting the capacitor electrodes. The resonators include a first resonator connected to an input terminal, a second resonator connected to an output terminal, and a third resonator between the first and second resonators. Shunt electrodes are connected to the via and the ground terminal in the first and second resonators, respectively.

According to one embodiment, a transformer-based in-phase and quadrature (IQ) includes a differential balun having a first inductor and a second inductor. The first inductor has a first input terminal and a first output terminal. The second inductor has a second input terminal and a second output terminal. Additionally, the IQ generator circuit includes a third inductor magnetically coupled with the first inductor. The third inductor has a first isolation terminal and a third output terminal. The IQ generator circuit also includes a fourth inductor magnetically coupled with the second inductor. The fourth inductor has a second isolation terminal and a fourth output terminal. The IQ generator circuit additionally includes a first transistor coupled to the first input terminal of the first inductor. Further, the generator circuit includes a second transistor coupled to the second input terminal of the second inductor. The first transistor, the second transistor, the first inductor, and the second inductor form a part of a differential amplifier.

A common-mode noise filter is provided, and comprises a first transmission structure and a second transmission structure. At least one first transmission unit is connected between a first signal input end and a first signal output end of the first transmission structure in series. At least one second transmission unit is connected between a second signal input end and a second signal output end of the second transmission structure in series. Two first capacitors are connected between the first signal input end and the second signal input end in series, and connected at a first node together. A first common-mode noise suppression unit is connected between the first node and a reference potential, and comprises a second capacitor and a first lossy element connected to the second capacitor in series or parallel. The first common-mode noise suppression unit can absorb a common-mode noise via the first lossy element.

Provided is a low-cost noise filter having a noise suppression effect that is not reduced even when a resonance frequency changes according to changes in temperature. A noise filter includes: a noise detection unit which detects a common mode noise; a cancellation signal output unit; an injection unit which injects a cancellation signal; and a grounded capacitor. The cancellation signal output unit includes a filter part which generates the cancellation signal from the common mode noise, and an amplification part which amplifies the cancellation signal. A temperature dependence of a product of an inductance value and a capacitance value of a main circuit portion including the noise detection unit, the injection unit, and the grounded capacitor, and a temperature dependence of a product of an inductance value and a capacitance value of the filter part, are equal to each other.

The present disclosure provides circuits and methods for fabricating circuits. A circuit may include an insulator having a first surface, a second surface, a periphery, a first subset of circuit elements disposed on the first surface, a second subset of circuit elements disposed on the second surface, and at least one conductive sidewall disposed on the periphery, wherein the conductive sidewall electrically couples the first subset of circuit elements to the second subset of circuit elements.