Patent ID: 8305160

Claim:
An elastic wave device comprising: a piezoelectric substrate; an unbalanced terminal provided on the piezoelectric substrate; first and second balanced terminals provided on the piezoelectric substrate; a plurality of ground terminals provided on the piezoelectric substrate; a longitudinally-coupled-resonator-type first elastic wave filter provided on the piezoelectric substrate; and a longitudinally-coupled-resonator-type second elastic wave filter provided on the piezoelectric substrate; wherein the first elastic wave filter includes first to third IDT electrodes arranged in order in an elastic wave propagation direction and two reflectors arranged on both sides in the elastic wave propagation direction of a region in which the first to third IDT electrodes are provided, one end of the second IDT electrode being connected to the first balanced terminal and the other end thereof being connected to the second balanced terminal; in the first elastic wave filter, one end of the first IDT electrode and one end of the third IDT electrode are connected to the unbalanced terminal and the other end of the first IDT electrode and the other end of the third IDT electrode are connected to at least one of the plurality of ground terminals; the second elastic wave filter includes first to third IDT electrodes arranged in order in an elastic wave propagation direction and two reflectors arranged on both sides in the elastic wave propagation direction of a region in which the first to third IDT electrodes are provided; in the second elastic wave filter, one end of the second IDT electrode is connected to the first balanced terminal and the other end thereof is connected to the second balanced terminal, one end of the first IDT electrode and one end of the third IDT electrode are connected to the unbalanced terminal, and the other end of the first IDT electrode and the other end of the third IDT electrode are connected to at least one of the plurality of ground terminals; a current path connecting the first elastic wave filter and the at least one of the plurality of ground terminals and a current path connecting the second elastic wave filter and the at least one of the plurality of ground terminals are different; and a number of the at least one of the plurality of ground terminals connected to the first elastic wave filter and a number of the at least one of the plurality of ground terminals connected to the second elastic wave filter are different from one another.