Impedance matching and parasitic capacitor resonance of FBAR resonators and coupled filters
US7391286B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 6, 2005 |
| Grant date | Jun 24, 2008 |
| Priority date | — |
| Expiry date | Mar 27, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/60
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A film acoustically-coupled transformer (FACT) has a first and a second stacked bulk acoustic resonator (SBAR 1, SBAR 2). Each SBAR has a stacked pair of film bulk acoustic resonators (FBARs) and an acoustic decoupler between the FBARs. Each FBAR has opposed planar electrodes and a layer of piezoelectric material between the electrodes. A first electrical circuit connecting one of the FBARs of SBAR1 to one of the FBARs of SBAR 2 and a second electrical circuit connecting the other of the FBARs of SBAR 1 to the other of the FBARs of SBAR 2. The first electrical circuit connects the respective FBARs in parallel and second electrical circuit connects the respective FBARs in series. A shunt inductor is included from the reception path to ground.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.