Disclosed herein are multi-layer metal circuits, such as printed circuit boards (PCBs), with single-sided, partially-shielded, or fully-shielded via-less common-mode filters. The multi-layer metal circuits comprise at least one shield layer, at least one signal trace, and at least one reference layer (e.g., ground). The reference layer comprises a pattern of the via-less common-mode filter. The pattern may comprise, for example, a single piece-wise linear segment, or two or more disjoint and non-intersecting segments (which may be strictly linear or piece-wise linear). The reference layer is electrically isolated from the shield layer, and thus the via-less common-mode filters do not require vias. In addition to being used in PCBs, the disclosed multi-layer metal circuits may also be used in other applications, such as integrated circuits (e.g., implemented in semiconductor chips).

A composite electronic component includes a main body including insulating layers, first and second input terminals, first and second output terminals, a ground terminal, first and second filters, and a resistance pattern connected between the second filter and the ground terminal. The first filter includes a first coil pattern connected between the first input terminal and the first output terminal, and a second coil pattern connected between the second input terminal and the second output terminal. The first and second coil patterns form a common mode filter. The second filter includes a third coil pattern connected between the first input terminal and the ground terminal, and a fourth coil pattern connected between the second input terminal and the ground terminal. The third and fourth coil pattern form a differential mode filter. The resistance pattern is on the insulating layer different from those of the first to fourth coil patterns.

A high-capacity common-mode inductor processing circuit for network signal is disclosed. Each of high-capacity common-mode inductors is disposed between two adjacent circuit channels to perform signal coupling, and each high-capacity common-mode inductor has parasitic capacitance between primary and secondary sides thereof, each of autotransformers is disposed on a side of corresponding one of the high-capacity common-mode inductors, and center tap lines of the autotransformers are grounded. The high-capacity common-mode inductor includes an iron core post and an iron core cover, the iron core post includes a winding part to be wound by conductive wires, and the conductive wires are wound on the winding part by a preset number of turns, and upwardly stacked and wound on the winding part by a preset layer number. The high-capacity common-mode inductors and the parasitic capacitances can eliminate noise on the circuit channels and perform signal coupling.

An electric compressor includes a compression part, an electric motor, an inverter device, and a housing. The inverter device includes an inverter circuit, a noise reduction unit, and a circuit board. The noise reduction unit includes a common mode choke coil and a smoothing capacitor. The common mode choke coil includes an annular core, a pair of winding wires, and an annular electrical conductor. The electrical conductor is split into a first metal plate and a second metal plate in a circumferential direction. The first metal plate is thermally coupled to the housing. The second metal plate is electrically connected to the first metal plate. An electrical resistance value of the first metal plate is larger than that of the second metal plate.

In some examples, a device is arranged to include a galvanic isolation barrier between first and second voltage domains. The device includes first and second capacitors arranged across the galvanic isolation barrier. The first and second capacitors are configured to communicate differential signals between the first and second domains. The device also includes a common mode suppression circuit arranged in the second voltage domain and configured to suppress a common mode signal communicated by the first and second capacitors. The common mode suppression circuit include a first passive RLC filter circuit coupled between the first capacitor and a low-impedance node. The common mode suppression circuit also includes a second passive RLC filter circuit coupled between the second capacitor and a low-impedance node.

The present invention provides an electrical filter device (1) for filtering a common-mode interference between a current source and a load, comprising:—a signal input (E), which comprises at least one first terminal (E1) and can be connected to the current source;—a signal output (A), which can be connected to the load;—a main stage (H0), having a first main inductor (2a), which comprises a coil with a first core (3), the first main inductor (2a) being connected to the first terminal (E1); and—an auxiliary stage (H1), having at least one first anti-interference capacitor (C1) and one first auxiliary inductor (4), the first auxiliary inductor (4) being connected between the first terminal (E1) and the first anti-interference capacitor (C1), the first auxiliary inductor (4) being inductively coupled to the first main inductor (2a).

An object of the present disclosure is to provide a common mode noise filter that can be used in a high-frequency band. The common mode noise filter of the present disclosure includes first to fifth insulator layers and stacked body in which first to fifth insulator layers are stacked along a vertical direction. The common mode noise filter further includes first spiral conductor and second spiral conductor that are formed inside stacked body and face each other across first insulator layer. The common mode noise filter further includes first pad connected to an inner end of first spiral conductor and second pad connected to an inner end of second spiral conductor. Neither first pad nor second pad overlaps each of first spiral conductor and second spiral conductor in top view.

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 noise filter (10) is equipped with a plurality of conductors (20) having respective winding portions (21) and a ring-shaped core (30) which is inserted through the winding portions of the a plurality of conductors and made of a magnetic material. The ring-shaped core is composed of a pair of divisional cores (41) and (42) which are combined together by joining each pair of joining surfaces (43) and (44), located at each end, of the pair of divisional cores and. The one divisional core is straight and is inserted through the winding portions of the a plurality of conductors. The other divisional core has partition walls (45) each of which is located between adjacent ones of the a plurality of conductors, projects toward the one divisional core, and serves to form a magnetic path between the partition wall and the one divisional core.

A circuit module includes a wiring board on which are provided a ground plane, a signal line, and a conductive pattern for connection to an outer conductor of a coaxial cable including an inner conductor and the outer conductor. A common-mode choke coil is mounted on the wiring board such that one of coils of the common-mode choke coil connects the ground plane and the conductive pattern and that the other coil is inserted in the signal line. A communication element is mounted on the wiring board and includes a first signal terminal and a second signal terminal. The first signal terminal is connected to the common-mode choke coil via the signal line, and the second signal terminal is connected to the ground plane. A first capacitor is inserted in series in the signal line between the common-mode choke coil and the first signal terminal.