Patent ID: 7808339

Claim:
A non-reciprocal circuit element comprising: permanent magnets; a ferrite arranged such that a direct current magnetic field is applied to the ferrite by the permanent magnets; a first center electrode disposed on the ferrite, one end of the first center electrode being electrically connected to an input port, and another end of the first center electrode being electrically connected to an output port; a second center electrode disposed on the ferrite, the second center electrode intersecting with the first center electrode while being electrically insulated from the first center electrode, one end of the second center electrode being electrically connected to an output port, the other end of the first center electrode being electrically connected to a ground port; a first matching capacitor electrically connected between the input port and the output port; a second matching capacitor electrically connected between the output port and the ground port; a resistor electrically connected between the input port and the output port; and a circuit board having a terminal electrode located on a surface thereof; wherein the ferrite and the permanent magnets define a ferrite magnet assembly in which the permanent magnets sandwich the ferrite so as to be substantially parallel to a surface of the ferrite having the first and second center electrodes disposed thereon; the ferrite magnet assembly is disposed on the circuit board so that the surface of the ferrite having the first and second center electrodes thereon is substantially perpendicular to a surface of the circuit board; and a planar yoke is disposed on an upper surface of the ferrite magnet assembly with a dielectric layer therebetween.