An inductive filtering device includes a first toric magnetic core without an air gap formed around a central void; a first electrical conductor formed of turns that are wound around the first magnetic core without passing through the central void, wherein no electrical conductor passes through the central void.

Disclosed herein is a common mode filter that includes a winding core part and first and second wires wound in a same direction around the winding core part. The first and second wires constitute a first winding block on one endmost side in an axial direction of the winding core part, a second winding block on other endmost side in the axial direction of the winding core part, and a third winding block positioned between the first and second winding blocks. The second winding block is a winding block at an odd-numbered position counted from the first winding block. The first and second wires cross each other in an area between the first and third winding blocks and in an area between the second and third winding blocks.

The invention relates to an electrical filter element (1) for filtering alternating voltage interference. The electrical filter element (1) comprises two dielectric circuit board substrates (11, 12) having a magnetic core (13) arranged between the circuit board substrates. The magnetic core (13) has a material-free inner region (13a), in which electrical connection elements (21-24) are provided between the two dielectric circuit board substrates (11, 12). Furthermore, electrical connection elements (31, 32) can also be provided between the two dielectric circuit board substrates (11, 12) in an outer region of the magnetic core (13).

A low pass filter is disclosed. In an embodiment a low-pass filter includes a current-compensated choke, a reference potential and a capacitor connected in parallel with the current-compensated choke and to the reference potential, wherein a core of the current-compensated choke is configured to have a magnetic circuit, and wherein the core has an air gap.

According to various embodiments, an example wireless power transmitter may include a transistor configured to output an amplified signal based on an input signal and a driving voltage, a first capacitor coupled to the transistor in parallel, a first LC resonant circuit coupled to the transistor in parallel and including a first inductor and a second capacitor coupled to the first inductor in series, a third capacitor having a first end coupled to an output terminal of the transistor and the first LC resonant circuit, a feeding coil coupled to a second end of the third capacitor in series, and having at least a part configured to form a second LC resonant circuit with the third capacitor, and a transmission resonator including a transmission coil and a fourth capacitor coupled to the transmission coil in series. At least a part of the transmission coil may be magnetically coupled with the feeding coil, and at least a part of power received from the feeding coil may be output to an outside through the transmission resonator.

Disclosed herein is a common mode filter that includes: a winding core part including first and second winding areas and a third winding area positioned between the first and second winding areas; and first and second wires wound in a same direction around the winding core part. The first and second wires constitute a first winding block wound in the first winding area and a second winding block wound in the second winding area. The first and second wires cross each other in the third winding area. Each of the first and second winding blocks has first and second winding layers. The difference in a number of turns between the first winding layer and the second winding layer is larger in the first winding block than in the second winding block.

Disclosed herein is a common mode filter that includes a winding core part and first and second wires wound in a same direction around the winding core part. The first and second wires constitute a first winding block on one endmost side in an axial direction of the winding core part, a second winding block on other endmost side in the axial direction of the winding core part, and a third winding block positioned between the first and second winding blocks. The second winding block is a winding block at an odd-numbered position counted from the first winding block. The first and second wires cross each other in an area between the first and third winding blocks and in an area between the second and third winding blocks.

Provided is a noise filter that can enhance noise removal performance with a simple configuration. A noise filter (10) includes a connector (20) that houses a terminal fitting (22) connected to an input/output wire (WH) in a state in which the input/output wire (WH) is lead out from the connector (20). The noise filter (10) includes a coil (40) that is connected to the input/output wire (WH), a capacitor (30) that is electrically connected to the coil (40), and a magnetic member (50). The noise filter (10) includes a case (60) that houses the capacitor (30), the coil (40), and the magnetic member (50), and a holding member (70) that holds the magnetic member (50) in a state in which the magnetic member (50) is positioned with respect to the coil (40).

Disclosed are a line filter and a power supply apparatus including the line filter. The line filter includes a first inductor having a first coil wound around a first bobbin; and a second inductor having a second coil wound around a second bobbin, the second inductor being induced by the first inductor to flow current, wherein the first bobbin and the second bobbin are physically separated from each other. The power supply apparatus includes such a line filter.

The invention is directed towards a power source interface module for electronic circuits supplied by power from a power source as well as a power supply arrangement for electronic circuits comprising such a power source interface module. The module comprises a first circuit board carrying components, the first circuit board comprising a number of stacked circuit board layers as well as at least two openings, at least a part of a filter comprising at least one pair of magnetically coupled inductive coils, a core with two core legs, each core leg stretching through a corresponding opening in the circuit board, wherein each coil is wound around a corresponding core leg, the turns of the coils stretch through the circuit board layers, and each layer between an upper outer layer and a lower outer layer comprises at least a part of one turn.