Surface acoustic wave filter device
    1.
    发明公开
    Surface acoustic wave filter device 失效
    AkustischeOberflächenwellenfilteranordnung。

    公开(公告)号:EP0562876A1

    公开(公告)日:1993-09-29

    申请号:EP93302371.5

    申请日:1993-03-26

    IPC分类号: H03H1/00 H03H9/145 H03H9/64

    CPC分类号: H03H9/643 H03H9/14505

    摘要: A surface acoustic wave filter device includes a substrate (1) which comprises quartz or the like piezoelectric having a small temperature coefficient and which is formed with unidirectional transducers (2,4) of asymmetrical construction. A floating electrode (12,13,16,17) is spaced from intermediate position between adjacent positive and negative electrodes (10,11,14,15) which are arranged in interdigital manner, to effectively utilize a mechanical reflection caused by the floating electrode. In consideration of the sign and magnitude of the reflection factor of the floating electrodes, short-circuited electrodes only are used for the floating electrodes. The surface acoustic wave filter device has improved temperature characteristic, insertion loss characteristic and phase characteristic.

    摘要翻译: 表面声波滤波器装置包括具有温度系数小的石英等压电体的基板(1),其形成有非对称结构的单向换能器(2,4)。 浮动电极(12,13,16,17)与相互正交和负极(10,11,14,15)之间的中间位置间隔开,它们以叉指方式布置,以有效地利用由浮动电极引起的机械反射 。 考虑到浮置电极的反射系数的符号和大小,短路电极仅用于浮置电极。 表面声波滤波器具有改善的温度特性,插入损耗特性和相位特性。

    Surface acoustic wave filter device
    4.
    发明公开
    Surface acoustic wave filter device 失效
    AkustischeOberflächenwellenfilteranordnung。

    公开(公告)号:EP0649219A1

    公开(公告)日:1995-04-19

    申请号:EP94307559.8

    申请日:1994-10-14

    IPC分类号: H03H9/00 H03H9/64 H03H9/145

    CPC分类号: H03H9/14505 H03H9/6426

    摘要: A surface acoustic wave filter device includes a piezoelectric substrate having mirror-polished surfaces on both sides, so that it is essentially free from warping. One surface of the substrate is provided with two filter stages which are cascade connected with each other thereby to sufficiently attenuate a bulk wave spurious noise below a practically negligible extent. The filter device can be manufactured with an improved yield.

    摘要翻译: 表面声波滤波器装置包括在两侧具有镜面抛光表面的压电基片,使得其基本上没有翘曲。 衬底的一个表面设置有彼此级联的两个滤波器级,从而充分地衰减低于实际可忽略的程度的体波杂散噪声。 过滤装置可以以提高的产量制造。