Patent ID: 7420435
Filing Date: 2008-09-02
Classification: H01P

Abstract:
1. A non-reciprocal circuit element comprising: permanent magnets; a ferrite arranged to receive a direct-current magnetic field from the permanent magnets; a plurality of center electrodes disposed on the ferrite; and a circuit substrate having a terminal electrode on a surface thereof; wherein the center electrodes include a first center electrode and a second center electrode including conducting films, the first and second center electrodes being insulated from each other and intersecting each other, the first center electrode having one end electrically connected to a first input-output port and the other end electrically connected to a second input-output port, the second center electrode having one end electrically connected to the second input-output port and the other end electrically connected to a third ground port; the permanent magnets have front and back substantially rectangular principal surfaces, and the ferrite has front and back substantially rectangular principal surfaces, the principal surfaces of the permanent magnets and the ferrite having substantially the same dimensions, the principal surfaces of the permanent magnets being arranged to face the principal surfaces of the ferrite such that outlines of the permanent magnets and an outline of the ferrite coincide with each other; and the ferrite has side surfaces that are substantially perpendicular to the principal surfaces thereof, the side surfaces being provided with recesses.