A common mode filter includes a body including a filter portion and an electrostatic protection portion, first to fourth external electrodes disposed on an external surface of the body, a ground electrode disposed on the external surface of the body, a first coil included in the filter portion and electrically connected to the first and second external electrodes, and a second coil included in the filter portion and electrically connected to the third and fourth external electrodes. The electrostatic protection portion includes discharge electrodes electrically connected to at least one of the first to fourth external electrodes and the ground electrode, a discharge part including conductive particles, a first organic-inorganic composite insulating layer disposed on the discharge electrodes and the discharge part, a magnetic cover layer disposed on the first organic-inorganic composite insulating layer, and a first inorganic insulating layer.

A common mode filter coupled to a protection device. In accordance with an embodiment, the common mode filter has first and second coils, each coil having a spiral shape, a central region, an exterior region, a first terminal, and a second terminal, wherein the first terminal of the first coil is formed in a first portion of the central region, the first terminal of the second coil is formed in a second portion of the central region, and wherein the central region is laterally bounded by the first and second coils and the exterior region is not surrounded by the first and second coils. The protection device has a first terminal coupled to the first terminal of the first coil and a second terminal coupled to the first terminal of the second coil.

A common mode inductor apparatus includes a magnetic core, a first coil winding and a second coil winding. The magnetic core has a first winding zone and a second winding zone. The first coil winding is wound in three winding areas within the first winding zone, wherein two neighboring winding areas within the first winding zone are separated by a gap. The second coil winding is wound in three winding areas within the second winding zone, wherein two neighboring winding areas within the second winding zone are separated by a gap.

The present invention discloses a signal processing device for processing a differential signal from a sensor at a prescribed signal frequency, having a positive signal input (5-1), which is couplable to a positive sensor output of the sensor, and a negative signal input (6-1), which is couplable to a negative sensor output of the sensor, having a positive signal output (7-1) and having a negative signal output (8-1), having a first frequency-dependent resistance (C1H) between the positive signal input (5-1) and the positive signal output (7-1) and having a second frequency-dependent resistance (C1L) between the negative signal input (6-1) and the negative signal output (8-1), wherein the first and second frequency-dependent resistances (C1H, C1L) are designed to allow electrical signals at the prescribed signal frequency to pass in approximately unattenuated fashion, having a first voltage divider (11), which is arranged at least in part in parallel with the first frequency-dependent resistance (C1H) and is designed to divide a voltage between the positive signal input (5-1) and the positive signal output (7-1) using a prescribed ratio, having a second voltage divider (12), which is arranged at least in part in parallel with the second frequency-dependent resistance (C1L) and is designed to divide a voltage between the negative signal input (6-1) and the negative signal output (8-1) using a prescribed ratio. Further, the present invention discloses a control device for an electric machine.

A device that filters electromagnetic interference includes electrical conductors mounted in parallel. Each conductor includes a first coil positioned between a first and a second end of the respective conductor. Each first coil is coupled magnetically to each other first coil and has the same number of turns as each other first coil. The first and second ends of each of the conductors, respectively, are first and second terminals for the device. The device includes capacitors. Each capacitor is mounted between the second end of a corresponding electrical conductor and a third terminal of the device. The device includes an additional circuit. The additional circuit includes a second coil coupled magnetically with the first coils of the conductors. The additional circuit includes an additional coil. The second coil has a second number of turns.

Disclosed herein is a common mode filter including: at least four coil layers, each layer having a primary coil and a secondary coil; and discontinuous parts made of an insulating material each extending between starting points of each of the primary coil and the secondary coil positioned on the lowest layer among the coil layers to ending points of each of the primary coil and the secondary coil positioned on the highest layer among the coil layers. The primary coils are connected in series from the lowest layer to the highest layer, and the secondary coils are connected in series from the lowest layer to the highest layer. The common mode filter is able to be miniaturized and has improved impedance characteristics.

The network filtering circuit includes a cable side for connection with a network cable, a physical side for connection with a mother board, and a plurality of transmission channels connected between the cable side and the physical side. Each of the transmission channels includes an isolation transformer with a primary coil connected with the cable side and a secondary coil coupling with the primary coil. A common mode choke has two first ends connected to the physical side and two opposite second ends. A pair of capacitors series connection with the corresponding second ends and are connected between the secondary coil and the common mode choke. The primary coil has a first center tap directly connected to a ground node.

The present disclosure provides a wrapping method for the common mode inductor. The common mode inductor includes a first coil winding and a second coil winding. The wrapping method for a common mode inductor includes steps of: disposing two isolation blocking sheets at different positions of a magnetic core; wrapping the first coil winding around the magnetic core, wherein the first coil winding is divided into two wrapping areas by one of the isolation blocking sheets; wrapping the second coil winding around the magnetic core, wherein the second coil winding is divided into two wrapping areas by the other one of the isolation blocking sheets, wherein the first coil winding and the second coil winding are symmetrically wrapped.

A board-type noise filter having higher noise removal performance than that of a conventional noise filter, and an electronic device including the board-type noise filter are provided. The board-type noise filter includes: a printed wiring board having a wiring pattern formed thereon; a choke coil including a core having a toroidal shape; a frame ground portion fixed to the printed wiring board at a position overlapping with a hollow portion of the choke coil when the toroidal shape of the choke coil is seen in plan view, the frame ground portion being capable of being grounded to a frame ground; and a capacitor having a first terminal connected to the frame ground portion through the wiring pattern.

A multilayer common mode filter includes a first coil, a second coil and a third coil. The first coil includes a first coil conductor and a second coil conductor having spiral shapes and is configured by electrically connecting the first coil conductor and the second coil conductor. The second coil includes a third coil conductor and a fourth coil conductor having spiral shapes and is configured by electrically connecting the third coil conductor and the fourth coil conductor. The third coil includes a fifth coil conductor and a sixth coil conductor having spiral shapes and is configured by electrically connecting the fifth coil conductor and the sixth coil conductor. The first to sixth coil conductors are disposed in order of the first coil conductor, the third coil conductor, the fifth coil conductor, the second coil conductor, the fourth coil conductor, and the sixth coil conductor in a first direction.