Variable transconductance amplifier
US6570427B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 31, 2001 |
| Grant date | May 27, 2003 |
| Priority date | — |
| Expiry date | Aug 31, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A variable transconductance amplifier including a variable attenuator stage coupled to a transconductance stage. The variable attenuator includes first and second differential to single-ended transconductance stages, each biased by a current device. The variable attenuator receives a differential input voltage signal and develops a current signal. At least one reactive element is coupled between the pair of differential to single-ended transconductance stages. The transconductance stage includes first and second differential pairs each having first and second control terminals and first and second output terminals. The first and second differential pairs are coupled to the first and second differential to single-ended transconductance stages, respectively, of the variable attenuator. The output terminals of the first and second differential pair are cross-coupled to develop a differential output current signal. The stages include electronically controllable current devices so that the overall transconductance decreases when the input signal increases without distorting the output signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.