US 7,532,084 B2
Nonreciprocal circuit element
Takaya Wada, Kanazawa (Japan); and Takashi Hasegawa, Omihachiman (Japan)
Assigned to Murata Manufacturing Co., Ltd, Kyoto (Japan)
Filed on Oct. 04, 2007, as Appl. No. 11/867,214.
Claims priority of application No. 2007-226641 (JP), filed on Aug. 31, 2007.
Prior Publication US 2009/0058551 A1, Mar. 05, 2009
Int. Cl. H01P 1/36 (2006.01)
U.S. Cl. 333—24.2 6 Claims
OG exemplary drawing
 
1. A non-reciprocal circuit element comprising:
a permanent magnet;
a ferrite arranged to receive a direct-current magnetic field from the permanent magnet;
a first center electrode disposed on the ferrite, one end of the first center electrode being electrically connected to an input port, and the other end of the first center electrode being electrically connected to an output port;
a second center electrode arranged on the ferrite so as to intersect the first center electrode with being insulated from the first center electrode, one end of the second center electrode being electrically connected to the output port, and the other end of the second 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
an inductor and a capacitor constituting an LC series resonant circuit electrically connected in parallel to the first center electrode and in series with the resistor between the input port and the output port.