Two-stage fully differential operational amplifier with efficient common mode feed-back circuit
US5955922A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 1997 |
| Grant date | Sep 21, 1999 |
| Priority date | — |
| Expiry date | Oct 22, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45711
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The circuit of a two-stage fully differential amplifier includes a differential input stage, two output stages and a common mode feedback circuit coupled to the output nodes of the amplifier. The amplifier also includes a non-inverting stage coupled to a respective output node of the differential input stage for driving the respective output stage. Each auxiliary non-inverting stage of the two branches of the fully differential amplifier uses as a biasing current generator, the load device of the branch of the differential input stage to the output of which the non-inverting stage is coupled. The fully differential amplifier permits the use of a null-consumption common mode feedback circuit as normally employed only in a single stage fully differential amplifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.