Patent ID: 7429901

Claim:
A non-reciprocal circuit element comprising: a permanent magnet; a ferrite member; a plurality of center electrodes coupled in a high frequency manner with the ferrite member to which a bias magnetic field is applied by the permanent magnet; wherein the ferrite member is provided with first, second, and third center electrodes; the first and third center electrodes do not intersect with each other, and intersect with the second center electrode in a mutually insulated state; connection is established so that a magnetic field generated when a current flows from one end to the other end of the first center electrode, and a magnetic field generated when a current flows from one end to the other end of the third center electrode have the same phase and direction; a first matching capacitor and a first terminating resistor are connected in parallel to the first center electrode, a second matching capacitor is connected in parallel to the second center electrode, and a third matching capacitor and a second terminating resistor are connected in parallel to the third center electrode; and one end of the first center electrode and the other end of the third center electrode define first balanced input/output ports, and the other end of the first center electrode, one end of the second center electrode, the other end of the second center electrode, and one of the third center electrode define second input/output ports.