Circuit for automatic volume compression or volume expansion
US4119922A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 26, 1977 |
| Grant date | Oct 10, 1978 |
| Priority date | — |
| Expiry date | Apr 26, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G7/004
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The circuit includes a signal path extending between an information signal input terminal and an information signal output terminal. A differential amplifier, having a non-inverting input and an inverting input, is included in the signal path, and a feedback path, containing electronically controlled impedance, connects the amplifier inverting input to the amplifier output. A branch path is branched off from the information signal output terminal and, in this branch path, a control voltage is derived from the information signal and fed to the electronically controllable impedance. In accordance with the invention, the information signal input terminal is connected to the non-inverting amplifier input to feed the information signal thereto. Two diodes are connected in parallel with each other, but in oppositely poled relation, across the feedback circuit, to limit the feedback voltage between the amplifier output and the amplifier inverting input. The circuit may be used in a so-called compander system, in which the control voltage is fed to a differential amplifier in the branch path having an inverting input connected, over a feedback path containing a second electronically contro…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.