Analog to digital converter, a digital to analog converter and an operational amplifier therefor
US4978959A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1989 |
| Grant date | Dec 18, 1990 |
| Priority date | — |
| Expiry date | Feb 27, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45508
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An operational amplifier is provided and includes at least two input terminals of one polarity and another input terminal of the opposite polarity. The amplifier includes an amplifying portion which comprises a differential section for receiving input signals applied to the input terminals. The differential section includes at least two differential amplifiers which form difference signals from the input signals. A summing section receives the difference signals and forms a sum result therefrom. A multiplying section provides an amplification gain to the sum result to form an output signal of desired gain. The amplifier is also provided with a feedback for applying an input signal to one of the input terminals, the output signal. The amplifier can be configured to provide amplification gains of 2, 1/2, -1 and 1. In view of the amplification gains equal to 2 and 1/2 respectively, there is also provided an analog to digital converter and a digital to analog converter both of which comprise a cascaded series of operational amplifiers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.