Automatic gain control circuit arrangements having a plurality of stages of amplification
US4001694A · kind A · utility
1Cited by
3References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 27, 1975 |
| Grant date | Jan 4, 1977 |
| Priority date | — |
| Expiry date | May 27, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R25/502
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Automatic gain control is provided in a two stage amplifier in which the first stage has a signal voltage gain related to its supply voltage and the second, or output, stage comprises an output transistor. The load of the output stage comprises an earphone in series with the supply. The supply for the first stage is taken from the junction of the output transistor and the earphone such that the gain varies inversely with the output of the earphone. The amplifier stages may be formed as a monolithic integrated circuit and contained in the housing of the earphone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.