发明名称 |
LADDER ACOUSTIC WAVE FILTER DEVICE AND BRANCHING FILTER |
摘要 |
A ladder acoustic wave filter device is constructed such that ripples in the pass band are suppressed, and insertion loss is small in both of a high frequency side portion and a low frequency side portion of the pass band. Apodization weighting is applied to a series-arm-side IDT electrode. Busbars of the series-arm-side IDT electrode are configured so that in an acoustic wave propagation direction, a distance in an overlap width direction between the busbars becomes shorter as the overlap width of electrode fingers becomes smaller. Each of a pair of comb-shaped electrodes of a parallel-arm-side IDT electrode further includes a plurality of dummy electrodes that extend from a busbar and are opposed to electrode fingers of the other comb-shaped electrode in the overlap width direction. The parallel-arm-side IDT electrode is a normal IDT electrode in which the overlap width is constant.
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申请公布号 |
US2013088305(A1) |
申请公布日期 |
2013.04.11 |
申请号 |
US201213686940 |
申请日期 |
2012.11.28 |
申请人 |
MURATA MANUFACTURING CO., LTD.;MURATA MANUFACTURING CO., LTD. |
发明人 |
TAKATA TOSHIAKI |
分类号 |
H03H9/64 |
主分类号 |
H03H9/64 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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