| 摘要 |
A saw filter of the invention has a piezoelectric substrate (11), plural numbers of IDT electrodes (12,13) arranged on a surface of the piezoelectric substrate (11) as well as on a first surface acoustic wave propagation path, reflector electrodes (14,15) arranged at least at both ends of a first electrode pattern formed including the plural IDT electrodes (12,13), one or more IDT electrodes (16) arranged on the surface of the piezoelectric substrate (11) as well as on a second surface acoustic wave propagation path which is different from the first surface acoustic wave propagation path and reflector electrodes arranged at least at both sides of a second electrode pattern formed including the IDT electrode (16), in which the IDT electrodes (12,13) on the first surface acoustic wave propagation path are electrically connected in series by connecting wirings (19) and the IDT electrode (16) on the second surface acoustic wave propagation path is connected between the connecting wirings (19) and the ground (20), which are arranged between the first electrode pattern and the second electrode pattern. According to this, the chip size can be made small.
|
