Variable gain amplifier
US4812781A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 7, 1987 |
| Grant date | Mar 14, 1989 |
| Priority date | — |
| Expiry date | Dec 7, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G3/10
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A differential variable gain transconductance amplifier suitable for but not limited to applications requiring operation with a power supply of less than 1.0V. The circuit is suitable for fabrication by integrated circuit technology and is composed of three major blocks: an input stage, a current summing gain control stage, and an output stage. The differential input stage is comprised of two identical voltage-to-current converters, with one used as the positive input and the other as the negative input. The current summing stage uses the principal of summation of opposite but equal currents canceling to produce attenuated gain. The output stage converts current into voltage and produces a single ended output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.