Patent ID: 8952767
Filing Date: 2015-02-10
Classification: H01P,H03H

Abstract:
1. A layered bandpass filter comprising: a layered structure including a plurality of dielectric layers that are stacked; an input terminal and an output terminal disposed on a periphery of the layered structure; and a first resonator, a second resonator, and a third resonator provided within the layered structure, wherein: of the first to third resonators, the first resonator is located closest to the input terminal, the third resonator is located closest to the output terminal, and the second resonator is located between the first resonator and the third resonator, in terms of circuit configuration; the first resonator includes a first inductor and a first capacitor; the second resonator includes a second inductor and a second capacitor; the third resonator includes a third inductor and a third capacitor; the second inductor is disposed at a position different from that of each of the first and third inductors in a stacking direction of the plurality of dielectric layers; no conductor layer is present between the second inductor and the first inductor and between the second inductor and the third inductor; the second inductor includes a first portion, a second portion, and a third portion; the first portion is elongated in one direction; the second portion and the third portion are connected to a same longitudinal end of the first portion; part of the second portion is opposed to part of the first inductor; part of the third portion is opposed to part of the third inductor; the first to third capacitors are disposed at positions different from those of the first to third inductors in the stacking direction; the second inductor is lower in inductance than the first and third inductors; and the second capacitor is higher in capacitance than the first and third capacitors.