Surface acoustic wave device and communication device incorporating same

摘要

In a surface acoustic wave device in which balanced terminals extend from series IDTs, noise coming from an electrical-potential signal at the series connection point of the series IDTs is removed to improve the degree of balance. A surface acoustic wave filter includes a pair of surface acoustic wave reflectors disposed on a piezoelectric substrate along the propagation direction of surface acoustic waves, and a plurality of IDTs disposed between the two surface acoustic wave reflectors. Two opposing electrode fingers of the IDTs, which are series IDTs, are connected to corresponding balanced terminals, and the series connection point thereof is grounded. As a result, noise coming from an abnormal electrical-potential signal generated at the series connection point is removed to improve the degree of balance between the balanced terminals.