发明名称 |
Surface acoustic wave filter device |
摘要 |
A ladder circuit type SAW filter device includes series arm resonators and parallel arm resonators that are defined by SAW resonators. Among the parallel arm resonators, a first parallel arm resonator that is connected to one of an input end and an output end and a second parallel arm resonator that is connected to a junction between two series arm resonators have the relationship of Cp1x2<CP2, where Cp1 represents the capacitance of the first parallel arm resonator and Cp2 represents the capacitance of the second parallel arm resonator. The inductance of an inductor that is connected to the second parallel arm resonator is equal to or less than the inductance of the inductor that is connected to the first parallel arm resonator. The SAW filter device has superior steepness of filter characteristics in the lower range of a pass band and outstanding attenuation in a stop band.
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申请公布号 |
US6819203(B2) |
申请公布日期 |
2004.11.16 |
申请号 |
US20020043140 |
申请日期 |
2002.01.14 |
申请人 |
MURATA MANUFACTURING CO., LTD. |
发明人 |
TANIGUCHI NORIO |
分类号 |
H03H9/145;H03H9/25;H03H9/64;(IPC1-7):H03H9/64;H03H9/72 |
主分类号 |
H03H9/145 |
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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