Disclosed herein is a common mode filter that includes first and second terminal electrodes provided on the first flange part, third and fourth terminal electrodes provided on the second flange part, a first wire wound around the winding core part and having one end connected to the first terminal electrode and other end connected to the third terminal electrode, and a second wire wound around the winding core part and having one end connected to the second terminal electrode and other end connected to the fourth terminal electrode. The winding core part includes a first winding region, a second winding region, and a third winding region positioned between the first and second winding regions in the axial direction. The first and second wires are bifilar-wound in the first and second winding regions and layer-wound in the third winding region.

An integrated circuit common-mode electromagnetic interference filter incorporating electro-static discharge protection comprising two inductive coils is provided. A pair of primary and secondary spiral inductor coils is disposed corresponding to each other. A dielectric layer is used to separate the primary spiral inductor coil from the secondary spiral inductor coil electrically. Resistivity of a high-resistance substrate is more than 100 Ω-cm for supporting the primary spiral inductor coil, the secondary spiral inductor coil and the dielectric layer thereon. The proposed filter structure can be formed in integrated circuit (IC) back-end processes and thus be extraordinarily advantageous of effectively eliminating electromagnetic interferences and having electrostatic protection effect at the same time, while having small footprint.

A circuit arrangement for an onboard network of a motor vehicle, includes a line having a first inductivity and connecting a component of a power electronics of an onboard network with an element, wherein the component is adapted for being clocked during operation of the power electronics at a clock frequency; and an absorber circuit assigned to the line and having a second inductivity and a capacitance, wherein the second inductivity of the absorber circuit is coupled with the first inductivity of the line.

A common mode choke coil includes a differential transmission line including first and second signal lines, a main circuit including a first coil provided in the first signal line, and a second coil provided in the second signal line and connected to the first coil by magnetic field coupling, and a parallel resonance circuit including a third coil connected to both the first and second coils by magnetic field coupling, and a first capacitor electrically connected in parallel to the third coil. In the common mode choke coil, a first resonant frequency of the main circuit is equal or substantially equal to a second resonant frequency of the parallel resonance circuit.

An all-pass filtering module of a common mode noise suppressing device includes first and second differential transmission circuits coupled to a reference node. Each of the first and second differential transmission circuits has an input terminal and an output terminal, and includes: first and second capacitive elements coupled in series between the input terminal and the output terminal; a first inductor coupled between the input terminal and the output terminal; and a third capacitive element and a second inductor coupled in series between the reference node and a common node between the first and second capacitive elements.

An advantageous effect of a low-pass filter that reduces high-frequency noise can be obtained by including an input terminal that extends from a front surface to a rear surface of a multilayer circuit board including a double-sided circuit board; a first wiring conductor having an end connected to the input terminal on the rear surface of the multilayer circuit board; a first via that extends from an other end of the first wiring conductor to the front surface of the multilayer circuit board; a second wiring conductor having an end connected to the first via on the front surface of the multilayer circuit board; and a first input capacitor disposed on the second wiring conductor; by being conductive due to the input terminal and the first via being configured in series; and including the first input capacitor.

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).

According to one embodiment, there is provided a multilayer substrate including a signal layer. The signal layer includes a first line and a second line which form a differential pair. The first line electrically connects a first node and a second node in the signal layer. The second line electrically connects a third node and a fourth node in the signal layer. The interval between the first line and the second line is approximately constant from the first node to the second node. A physical length from the third node to the fourth node in the second line is shorter than a physical length from the first node to the second node in the first line. A width of the second line is thicker than a width of the first line.

Disclosed are a common mode filter and a manufacturing method thereof. The common mode filter in accordance with an aspect of the present invention includes: a substrate; a filter layer including a coil and a dielectric layer and disposed on the substrate and configured to remove a signal noise; and a magnetic layer being laminated on the filter layer, and a surface of the filter layer being joined with the magnetic layer can be formed to be flat by having the coil embedded in a surface of the filter layer being joined with the magnetic layer in such a way that one surface of the coil is exposed.

A noise filter includes a first capacitor and a second capacitor which are two line-to-line capacitors. Currents flowing through the first capacitor and the second capacitor are in directions opposite to each other, and meanwhile, currents flowing through a first connection wire and a second connection wire are in the same direction and parallel to each other. Accordingly, magnetic coupling is caused between the connection wires and the line-to-line capacitors. Thus, the residual inductance of a line-to-line capacitor itself is reduced, whereby an attenuation characteristic for normal mode noise is further improved.