Preamplifier circuit for a microelectromechanical capacitive acoustic transducer
US9350305B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 8, 2013 |
| Grant date | May 24, 2016 |
| Priority date | — |
| Expiry date | May 3, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2201/003
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Described herein is a preamplifier circuit for a capacitive acoustic transducer provided with a MEMS detection structure that generates a capacitive variation as a function of an acoustic signal to be detected, starting from a capacitance at rest; the preamplifier circuit is provided with an amplification stage that generates a differential output signal correlated to the capacitive variation. In particular, the amplification stage is an input stage of the preamplifier circuit and has a fully differential amplifier having a first differential input (INP) directly connected to the MEMS detection structure and a second differential input (INN) connected to a reference capacitive element, which has a value of capacitance equal to the capacitance at rest of the MEMS detection structure and fixed with respect to the acoustic signal to be detected; the fully differential amplifier amplifies the capacitive variation and generates the differential output signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.