Filter and multiplexer

Abstract

A filter having a pass band includes a series circuit in which a series arm resonator and a first inductor are connected in series with each other and which forms at least part of a signal path R connecting a first input/output terminal and a second input/output terminal and a parallel arm resonator connected between one end of the series circuit and a ground. The series circuit becomes inductive in the pass band. An anti-resonant frequency of the series arm resonator is higher than a frequency at a higher-frequency end of the pass band. A resonant frequency of the parallel arm resonator is higher than the anti-resonant frequency of the series arm resonator.

Dependencies are inferred from the claim text.