Disclosed herein is an electronic circuit module that includes a circuit board and a common mode filter mounted on the circuit board. The common mode filter includes first and second terminal electrodes constituting a first pair of terminal electrodes and third and fourth electrodes constituting a second pair of terminal electrodes. The circuit board includes: a first wiring layer having first, second, third, and fourth land patterns connected to the first, second, third, and fourth terminal electrodes, respectively, and first, second, third, and fourth wiring patterns connected to the first, second, third, and fourth land patterns, respectively; and a second wiring layer having a ground pattern that overlaps the first, second, third, and fourth wiring patterns without overlapping the first and second land patterns.

This on-vehicle power conversion apparatus is provided with: a power conversion circuit to which DC power is inputted; and a noise reduction unit that is configured to reduce common-mode noise and normal-mode noise which are included in the DC power and that is provided to the input side of the power conversion circuit. The noise reduction unit is provided with: a core having a first core part and a second core part; a common-mode chalk coil having a first winding wire wound around the first core part and a second winding wire wound around the second coil part; and a smoothing capacitor that constitutes a low-pass filter circuit cooperatively with the common-mode chalk coil. The power conversion apparatus is further provided with a damping unit provided at a position intersecting the magnetic path of a magnetic flux leakage.

A filter that includes a series circuit of a first Zener diode and a second Zener diode, a third Zener diode connected between a node and ground, and a third inductor. A first series resonant circuit is formed by a parasitic capacitance of the first Zener diode, a parasitic capacitance of the third Zener diode, and the third inductor, and a second series resonant circuit is formed by a parasitic capacitance of the second Zener diode, the parasitic capacitance of the third Zener diode, and the third inductor. Moreover, the parasitic capacitances of the first Zener diode and the second Zener diode are substantially equal, and the parasitic capacitance of the third Zener diode is larger than the parasitic capacitance of each of the first Zener diode and the second Zener diode.

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 is provided with a filter circuit including a first condenser and a second condenser; the first condenser and the second condenser are connected in parallel with each other by a first wiring lead for connecting one terminal of the first condenser with one terminal of the second condenser and a second wiring lead for connecting the other terminal of the first condenser with the other terminal of the second condenser; the first wiring lead and the second wiring lead are arranged in such a way as to intersect each other odd-number times.

A device and method for reducing ground currents and electromagnetic interference in pulsed signal devices are described. In one embodiment, the device may include, in addition to regular filtering components and circuits, a separate noise-suppressing choke in the ground wire to reduce current in the ground wire that causes damage to bearings and electrical overstress. Such choke may be of a saturation type that offers high inductance and good noise-blocking properties in normal operating conditions and sufficiently low impedance at fail currents which provides proper tripping of safety circuits.

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.

This on-vehicle power conversion apparatus is provided with: a power conversion circuit to which DC power is inputted; and a noise reduction unit that is configured to reduce common- mode noise and normal-mode noise which are included in the DC power and that is provided to the input side of the power conversion circuit. The noise reduction unit is provided with: a core having a first core part and a second core part; a common-mode chalk coil having a first winding wire wound around the first core part and a second winding wire wound around the second coil part; and a smoothing capacitor that constitutes a low-pass filter circuit cooperatively with the common-mode chalk coil. The power conversion apparatus is further provided with a damping unit provided at a position intersecting the magnetic path of a magnetic flux leakage.

The invention which relates to an EMC filter for the suppression of interference signals addresses the problem of specifying a solution with which reworking expenditures of an inverter board are reduced and, additionally, installation space restriction as well as reduction of development and production costs are attained. This problem is resolved thereby that in an EMC filter module at least one core of a choke with a winding is disposed on a first mounting board, that at least one of the capacitors is disposed on the first mounting board, that the first mounting board comprises at least two contact means and that the first mounting board of the EMC filter module is disposed with its contact means on a main board of an inverter and is electrically connected thereto.

In a power converter having a semiconductor switch, common-mode noise is effectively reduced by setting the common-mode inductance value of reactors which are inserted into both lines such that the resonance frequency of the combined capacity of a line-to-ground bypass capacitor and the reactors which are inserted into both lines becomes a predetermined value or more.