Surface acoustic wave apparatus

摘要

A SAW apparatus includes a plurality of IDTs disposed on a piezoelectric substrate, and an edge-reflection-type SAW device in which surface acoustic waves are reflected by the edge surfaces of the piezoelectric substrate. The SAW device is housed in a package. On the top of a first main surface of the piezoelectric substrate, first and second pyroelectric charge cancellation electrodes are disposed in the vicinity of the edges defined by the main surface and the side surfaces. The first and second pyroelectric charge cancellation electrodes are electrically connected to the electrodes on the package which are electrically connected to each other within the package, respectively. Therefore, the adverse effects of pyroelectric charge which is generated due to a rapid change in temperature is minimized.