Band-pass filter using film bulk acoustic resonator
US6885262B2 · kind B2 · utility
55Cited by
1References
3Claims
0Family size
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Key dates
| Filing date | Oct 30, 2003 |
| Grant date | Apr 26, 2005 |
| Priority date | — |
| Expiry date | Oct 30, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2003/0457
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A band-pass filter has a ladder-type circuit including first and second terminals whose characteristic impedances are Z0, and series elements and shunt elements disposed between a first terminal and a second terminal, each of the series elements and shunt elements containing a film bulk acoustic resonator. Assuming that characteristic impedance of any one of the series elements is Z1 and that characteristic impedance of any one of the shunt elements is Z2, the characteristic impedances Z0, Z1, and Z2 have a relation of 1<(Z1/Z0)<2, preferably 1.3<(Z1/Z0)<1.7, and 0.5<(Z2/Z0)<1, preferably 0.6<(Z2/Z0)<0.8.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.