Minimizing changes in common mode voltage at inputs of an operational amplifier used in a switched capacitor differential amplifier
US7795958B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 2008 |
| Grant date | Sep 14, 2010 |
| Priority date | — |
| Expiry date | Nov 3, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45588
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A reference generation circuit provided according to an aspect of the present invention generates a reference potential at different levels in the hold phase of different cycles in an input path of a switched capacitor differential amplifier. In an embodiment, for each hold phase, the reference generator provides the reference potential with a magnitude that tracks the magnitude of the input signal applied in a corresponding (preceding) sample phase. In case of a single-ended output, the reference potential generated for each hold phase equals the magnitude of one of the inputs on the differential input path. As a result, the common mode voltage at the input terminals of an operational amplifier contained in the switched capacitor differential amplifier is maintained at a desired level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.