| 摘要 |
A second band pass filter that is used in a filter device, which has a relatively high pass band, in the pass band of a first band pass filter is provided. One end of a second IDT of a second longitudinally coupled resonator surface acoustic wave filter portion is connected to a first balanced terminal and the other end thereof is connected to a second balanced terminal. Each of a first longitudinally coupled resonator surface acoustic wave filter portion and the second longitudinally coupled resonator surface acoustic wave filter portion has narrow pitch electrode finger portions. The number of electrode fingers of the narrow pitch electrode finger portion of the second IDT of the first longitudinally coupled resonator surface acoustic wave filter portion is greater than the number of electrode fingers of the narrow pitch electrode finger portion of the second IDT of the second longitudinally coupled resonator surface acoustic wave filter portion.
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