Patent ID: 9166549
Filing Date: 2015-10-20
Classification: H01P,H03H

Abstract:
1. A high-frequency filter comprising: a laminated body including a plurality of insulator layers stacked on each other in a lamination direction; three or more LC parallel resonators each including a capacitor and a coil and aligned in a predetermined direction; and a floating conductor arranged to not contact with other conductors; wherein adjacent ones of the three or more LC parallel resonators are electromagnetic-field-coupled to each other; each of the capacitors of the three or more LC parallel resonators includes a ground conductor provided within the laminated body and a resonance capacitor conductor facing the respective ground conductor and generating capacitance; each of the coils of the three or more LC parallel resonators includes a first via conductor penetrating one or more insulator layers of the plurality of insulator layers, a second via conductor penetrating one or more insulator layers of the plurality of insulator layers, and a line conductor provided on one of the plurality of insulator layers, the line conductor being respective electrically connected to the corresponding resonance capacitor conductor through the corresponding first via conductor and electrically connected to the corresponding ground conductor through the corresponding second via conductor; the resonance capacitor conductor and the ground conductors of each of the three or more LC parallel resonators are located on one side with respect to the respective line conductor of each of the three or more parallel resonators in the lamination direction; the floating conductor is provided astride the coils of the three or more LC parallel resonators; a sum of electrostatic capacitance generated between a first line conductor and the floating conductor and a second line conductor and the floating conductor is larger than a sum of electrostatic capacitance generated between the resonance capacitor conductor of each of the three or more LC parallel resonators and the floating conductor; the first line conductor and the second line conductor are from among the line conductors of the three or more LC parallel resonators overlapping with the floating conductor in a planar view from the lamination direction; the first line conductor being located at one end in the predetermined direction; the second line conductor being located at another end in the predetermined direction; and in the planar view from the lamination direction, an area where the floating conductor and the ground conductor overlap with each other is smaller than a sum of areas where the floating conductor and the first line conductor and the floating conductor and the second line conductor overlap with each other.