Patent ID: 9083306
Filing Date: 2015-07-14
Classification: H03H

Abstract:
1. A band-pass filter comprising: an input terminal; an output terminal; at least one LC parallel resonator arranged between the input terminal and the output terminal, the at least one LC parallel resonator including one end that is grounded; at least one trap resonator arranged between the at least one LC parallel resonator and at least one of the input terminal and the output terminal, the at least one trap resonator being arranged to be electromagnetically coupled to the at least one LC parallel resonator; a plurality of dielectric layers; a plurality of electrode layers respectively located on the plurality of dielectric layers, the plurality of dielectric layers and the plurality of electrode layers being stacked on one another; wherein an inductor of the at least one LC parallel resonator and an inductor of the at least one trap resonator each include a via electrode penetrating through the plurality of dielectric layers and a line electrode layer located on one of the plurality of dielectric layers; a capacitor of the at least one LC parallel resonator includes a capacitor electrode layer and a ground electrode layer that face each other; the inductor of the at least one LC parallel resonator has a substantially loop shaped configuration including the respective line electrode layer, the respective via electrode that establishes an electrical connection between one of two ends of the respective line electrode layer and the capacitor electrode layer, and a second via electrode that establishes an electrical connection between the other end of the respective line electrode layer and the ground electrode layer; a capacitor of the at least one trap resonator includes a pair of capacitor electrode layers that face each other; the inductor of the at least one trap resonator has a substantially loop shaped configuration including the respective line electrode layer, the respective, the via electrode that establishes an electrical connection between one of two ends of the respective line electrode layer and one of the pair of capacitor electrode layers, and a respective via electrode that establishes electrical connection between the other end of the respective line electrode layer and the one other of the pair of capacitor electrode layers; the at least one LC parallel resonator includes a plurality of LC parallel resonators; and the capacitor electrode layer of a first LC parallel resonator, among the plurality of LC parallel resonators, which is closest to the at least one trap resonator, and the one of the pair of capacitor electrode layers of the at least one trap resonator face a coupling electrode layer located on one of the plurality of dielectric layers, across respective dielectric layer thereof, and the first LC parallel resonator and the at least one trap resonator are electromagnetically coupled to each other via the coupling electrode layer.