Stereo expansion selection switch
US5208493A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1991 |
| Grant date | May 4, 1993 |
| Priority date | — |
| Expiry date | Apr 30, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R5/04
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A stereo expansion circuit has right and left amplifying channels for providing expanded stereo signals. A selection device comprises a switch cross coupling the signal channels for providing expanded stereo when the switch is closed. Circuitry is provided for preventing the switching control signal from being coupled to the signal channels. More specifically, a version of a signal coupled between the signal channels through the conduction channel of the switch is applied to the control input of the switch to inhibit the control signal from being coupled to the conduction channel. Such an arrangement is particularly advantageous when the switch comprises a J-FET.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.