Title:
平衡型弾性表面波フィルタ
Document Type and Number:
Japanese Patent JP4548418
Kind Code:
B2
Abstract:
To provide means for improving a guaranteed attenuation of a cascade-connected unbalanced-balanced double-mode SAW filter. An unbalanced-balanced SAW filter is configured by providing two cascade-coupled primary-tertiary double-mode SAW filters on a piezoelectric substrate along a propagation direction of a surface wave in parallel and cascade-connecting them, connecting one of electrodes of an IDT of a first double-mode SAW filter disposed at a central portion to a first port Port1, and connecting one of electrodes of an IDT of a second double-mode SAW filter disposed at a central portion to a second port Port2, and connecting the other electrode thereof to a third port Port3. The SAW filter is configured by disposing an electrode near the surroundings of the first port Port1 and the third port Port3 and connecting the electrode to a lead electrode provided at a peripheral edge of the piezoelectric substrate.
Inventors:
Shozo Matsumoto
Application Number:
JP2006512341A
Publication Date:
September 22, 2010
Filing Date:
April 12, 2005
Export Citation:
Assignee:
Epson Toyocom Corporation
International Classes:
H03H9/64; H01L41/09; H01L41/18; H03H9/00; H03H9/02; H03H9/145; H03H9/25
Domestic Patent References:
| JP2003060484A | 2003-02-28 | |||
| JP2003218670A | 2003-07-31 | |||
| JP2000312125A | 2000-11-07 | |||
| JP2003204243A | 2003-07-18 | |||
| JP2002084164A | 2002-03-22 |
Attorney, Agent or Firm:
Hitoshi Suzuki