Variable gain amplifier circuit
US5581213A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Dec 3, 1996 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G1/0088
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A non-attenuating automatic variable gain amplifier (VGA) circuit includes an operational amplifier (op amp) with a feedback resistor connected between its output and inverting input terminals. A variable gain setting resistance circuit having a variable resistance is the gain setting resistor positioned between the op amp's inverting input and a low voltage supply. By varying the resistance of the variable resistance circuit, the gain of the VGA circuit can be manipulated without requiring attenuation of the input signal. A resistance setting control for the variable resistance circuit can operate open loop, fed back from the amplifier output, or fed forward from the amplifier input.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.