Patent ID: 7463120
Filing Date: 2008-12-09
Classification: H01P

Abstract:
1. A high frequency filter comprising: a layered substrate including dielectric layers and conductor layers that are alternately stacked; a first resonator and a second resonator that are formed of part of the conductor layers inside the layered substrate and that are inductively coupled to each other; at least one group of first to fourth electrodes that are formed of part of the conductor layers inside the layered substrate and that capacitively couple the first and second resonators to each other; at least one first through hole provided inside the layered substrate and connecting the first resonator to the first electrode; and at least one second through hole provided inside the layered substrate and connecting the second resonator to the second electrode, wherein: the third electrode is connected to the second resonator and opposed to the first electrode with one of the dielectric layers inside the layered substrate disposed in between; the fourth electrode is connected to the first resonator and opposed to the second electrode with one of the dielectric layers inside the layered substrate disposed in between; and the first capacitor is formed of the first and third electrodes and the one of the dielectric layers located between the first and third electrodes, and the second capacitor connected to the first capacitor in parallel is formed of the second and fourth electrodes and the one of the dielectric layers located between the second and fourth electrodes.