Microphone circuit
US6104818A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 22, 1997 |
| Grant date | Aug 15, 2000 |
| Priority date | — |
| Expiry date | Apr 22, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R3/00
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A microphone circuit with low distortion and having the capability of an electronic volume control. The circuit includes a capacitor microphone cap provided with a field effect transistor at the output end and a capacitor connected to the output end of the microphone cap. A resistance for supplying a driver voltage to the microphone circuit is connected to a connecting point between the microphone cap and the capacitor. Preferably a transistor adapted to generate a driver voltage for the microphone circuit or an electronic valve is connected between the microphone cap and the connecting point. The emitter of the transistor is then connected to the collector of the field effect transistor and the collector of the transistor is connected to the connecting point.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.