Patent ID: 6919777

Claim:
A surface acoustic wave filter device comprising: a surface acoustic wave filter element including a piezoelectric substrate and a plurality of one terminal pair surface acoustic wave elements provided on said piezoelectric substrate, said plurality of one terminal pair surface acoustic wave elements being connected so as to define a parallel arm resonator and a series arm resonator in a ladder circuit; a package accommodating said surface acoustic wave filter element; said surface acoustic wave filter element being bonded via a plurality of bumps by a face down mounting process and being accommodated in said package; and an inductance component defined by a microstrip line which is provided in said package and connected to at least one of said series arm resonator and said parallel arm resonator; wherein the package includes a die-attach portion including a plurality of electrode pads which are connected via said plurality of bumps to one of a signal terminal and a ground terminal of the surface acoustic wave filter element; at least a majority of the inductance component is located outside an area defined by the die-attach portion; said package includes a plurality of external electrodes which are electrically connected to at least one of said plurality of electrode pads, and connected to one of a signal line and a ground line outside the surface acoustic wave filter device; and said microstrip line is connected between said electrode pad connected to the signal terminal of said series arm resonator and said external electrode connected to the signal line outside said surface acoustic wave filter device.