Patent ID: 8659368

Claim:
A surface acoustic wave filter device comprising: first and second signal terminals; a surface acoustic wave filter portion connected between the first signal terminal and the second signal terminal and including a plurality of surface acoustic wave resonators; a surface acoustic wave filter chip in which the plurality of surface acoustic wave resonators are provided; and a wiring board including first and second principal surfaces, the surface acoustic wave filter chip being mounted on the first principal surface, the first and second signal terminals being provided on the second principal surface, the wiring board including a plurality of land electrodes provided on the first principal surface and connected to the surface acoustic wave filter chip, and a wiring electrode provided on the first principal surface and connected to at least one of the plurality of land electrodes; wherein the surface acoustic wave filter chip includes a piezoelectric substrate and IDT electrodes that are provided on a surface of the piezoelectric substrate that faces the wiring board, and that define the plurality of surface acoustic wave resonators; and an IDT electrode defining any one of the plurality of surface acoustic wave resonators except for the IDT electrode having a smallest amount of heat generation per unit time when a signal flows between the first and second signal terminals, does not face the wiring electrode.