Abstract: A band-pass filter includes a first input/output port, a second input/output port, a plurality of resonators, and a multilayer stack. The multilayer stack includes a plurality of stacked dielectric layers. Each of the resonators is an open-ended resonator formed of a conductor line in the multilayer stack. Each of the resonators includes a resonator conductor portion including a first line part and a second line part located away from each other in a direction orthogonal to a stacking direction of the plurality of dielectric layers, and a third line part connecting the first line part and the second line part. The first to third line parts extend to surround a space between the first line part and the second line part.

Abstract: A filter circuit includes a pair of balanced input ports, a pair of balanced output ports, first and second resonators provided in parallel between the pair of balanced input ports and the pair of balanced output ports in a circuit configuration, a first capacitor connected in parallel to the first resonator, and a second capacitor connected in parallel to the second resonator. The first and second resonators are magnetically coupled to each other and electrically connected to each other. The first and second capacitors are not electrically connected to ground.

Abstract: A filter circuit includes a pair of balanced input ports, a pair of balanced output ports, and first and second resonators provided in parallel between the pair of balanced input ports and the pair of balanced output ports in a circuit configuration, the first and second resonators being magnetically coupled to each other. Between the first resonator and the second resonator, a capacitor is present but no inductor is present in the circuit configuration.

Abstract: A band-pass filter includes an unbalanced port, a first balanced port, a second balanced port, and first to third resonators provided between the unbalanced port and the first and second balanced ports. The second resonator and the third resonator each are a resonator with both ends open. The second resonator and the third resonator are adjacent to each other in a circuit configuration, and electromagnetically coupled by magnetic coupling as main coupling. The first resonator is provided closer to the second resonator than to the third resonator, and jump-coupled to the third resonator.

Abstract: A band-pass filter includes an unbalanced port, a first balanced port, a second balanced port, and first to third resonators provided between the unbalanced port and the first and second balanced ports. The second resonator and the third resonator each are a resonator with both ends open. The second resonator and the third resonator are adjacent to each other in a circuit configuration, and electromagnetically coupled by magnetic coupling as main coupling. The first resonator is provided closer to the second resonator than to the third resonator, and jump-coupled to the third resonator.

Abstract: A band-pass filter includes an unbalanced port, a first balanced port, a second balanced port, and first to third resonators provided between the unbalanced port and the first and second balanced ports. The second resonator and the third resonator each are a resonator with both ends open. The second resonator and the third resonator are adjacent to each other in a circuit configuration, and electromagnetically coupled by magnetic coupling as main coupling. The first resonator is provided closer to the second resonator than to the third resonator, and jump-coupled to the third resonator.

Abstract: A band-pass filter includes a first input/output port, a second input/output port, a plurality of resonators, and a multilayer stack. The multilayer stack includes a plurality of stacked dielectric layers. Each of the resonators is an open-ended resonator formed of a conductor line in the multilayer stack. Each of the resonators includes a resonator conductor portion including a first line part and a second line part located away from each other in a direction orthogonal to a stacking direction of the plurality of dielectric layers, and a third line part connecting the first line part and the second line part. The first to third line parts extend to surround a space between the first line part and the second line part.

Abstract: Disclosed herein is a nonreciprocal circuit element that includes a magnetic rotator disposed between first and second ground conductors, and a permanent magnet that applies a DC magnetic field to the magnetic rotator. The magnetic rotator includes a first ferrite core having a first surface covered with the first ground conductor, a second ferrite core having a second surface covered with the second ground conductor, a first center conductor directly fixed to a third surface of the first ferrite core positioned opposite to the first surface, and a second center conductor directly fixed to a fourth surface of the second ferrite core positioned opposite to the second surface.

Abstract: A band-pass filter includes an unbalanced port, a first balanced port, a second balanced port, and first to third resonators provided between the unbalanced port and the first and second balanced ports. The second resonator and the third resonator each are a resonator with both ends open. The second resonator and the third resonator are adjacent to each other in a circuit configuration, and electromagnetically coupled by magnetic coupling as main coupling. The first resonator is provided closer to the second resonator than to the third resonator, and jump-coupled to the third resonator.

Abstract: Disclosed herein is a nonreciprocal circuit element that includes a permanent magnet, a magnetic material having an insulating property, a magnetic rotator sandwiched between the permanent magnet and the magnetic material, and an external terminal. The magnetic rotator includes a center conductor connected to the external terminal, and first and second ferrite cores sandwiching the center conductor. The external terminal covers a side surface of the magnetic material without covering a side surface of the permanent magnet.

Abstract: Disclosed herein is a nonreciprocal circuit element that includes a magnetic rotator, and a permanent magnet that applies a DC magnetic field to the magnetic rotator. The magnetic rotator includes a center conductor, a first ferrite core laminated on the center conductor, and a dielectric provided in a gap formed between the center conductor and the first ferrite core.

Abstract: Disclosed herein is a nonreciprocal circuit element that includes a magnetic rotator disposed between first and second ground conductors, and a permanent magnet that applies a DC magnetic field to the magnetic rotator. The magnetic rotator includes a first ferrite core having a first surface covered with the first ground conductor, a second ferrite core having a second surface covered with the second ground conductor, a first center conductor directly fixed to a third surface of the first ferrite core positioned opposite to the first surface, and a second center conductor directly fixed to a fourth surface of the second ferrite core positioned opposite to the second surface.

Abstract: Disclosed herein is a nonreciprocal circuit element that includes a permanent magnet, a magnetic material having an insulating property, a magnetic rotator sandwiched between the permanent magnet and the magnetic material, and an external terminal. The magnetic rotator includes a center conductor connected to the external terminal, and first and second ferrite cores sandwiching the center conductor. The external terminal covers a side surface of the magnetic material without covering a side surface of the permanent magnet.

Abstract: Disclosed herein is a nonreciprocal circuit element that includes a magnetic rotator, and a permanent magnet that applies a DC magnetic field to the magnetic rotator. The magnetic rotator includes a center conductor, a first ferrite core laminated on the center conductor, and a dielectric provided in a gap formed between the center conductor and the first ferrite core.

Abstract: A non-reciprocal circuit element includes a plurality of inner conductors intersecting with keeping insulation with each other, a shield conductor connected in common to one end of the inner conductors, and a capacitor connected between the shield conductor and a ground of the non-reciprocal circuit element, for adjusting only eigen values of in-phase excitation. Thus, smaller size, lighter weight and lower height can be attained and also temperature characteristics can be optionally adjusted without changing material used and without inviting increased insertion loss.