Read-out circuit with high input impedance
US8300850B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 2009 |
| Grant date | Oct 30, 2012 |
| Priority date | — |
| Expiry date | Apr 5, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R3/00
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Provided is a read-out circuit that is connected to a microphone and configured to linearly amplify a current signal generated by the microphone and output the amplified current signal. The read-out circuit includes an amplification unit and a feedback resistor. The amplification unit has an amplification gain between 0 and 1. The feedback resistor is connected between input and output terminals of the amplification unit. As the amplification gain of the amplification unit becomes closer to 1, an input impedance becomes higher. A preamp of the read-out circuit can have a high input impedance due to the amplification gain, and the read-out circuit can be manufactured using a CMOS process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.