Digital microphone
US7899196B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 9, 2005 |
| Grant date | Mar 1, 2011 |
| Priority date | — |
| Expiry date | May 27, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R19/04
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An integrated circuit, configured to process microphone signals, where the integrated circuit comprises: a preamplifier (306) with an amplifier section (301) which has a first input (φ) and a second input (φ*) and an output (φ), and with a feedback filter network (Z1; Z1, Z1*, Z2) coupled between the output (φ; φ, φ*) and the second input (φ′); where the first input (φ) to the amplifier section (301) has an input impedance which by means of the input impedance of the amplifier section is substantially isolated from the feedback network with respect to input impedance; and where the preamplifier has a frequency-gain transfer function which suppress low frequencies; and an analogue-to-digital converter coupled to receive an anti-aliasing filtered input signal and providing a digital output signal (Do).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.