Switched-capacitor band-pass filter of a discrete-time type, in particular for cancelling offset and low-frequency noise of switched-capacitor stages
US9106208B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 2013 |
| Grant date | Aug 11, 2015 |
| Priority date | — |
| Expiry date | Jan 28, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H19/004
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A band-pass filter made up by an operational amplifier and by an input circuit. The input circuit is formed by a capacitive filtering element, connected to the input of the operational amplifier; a coupling switch, coupled between an input node and the capacitive filtering element; a capacitive sampling element, coupled between the input of the filter and the input node; and a sampling switch, coupled between the input node and a reference-potential line. The coupling switch and the input sampling switch close in phase opposition according to a succession of undesired components sampling and sensing steps, so that the capacitive sampling element forms a sampler for sampling the undesired component in the undesired components sampling step, in the absence of the component of interest, and forms a subtractor of the undesired components from the input signal in the sensing step.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.