Sigma delta converter with flying capacitor input
US7230555B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 2005 |
| Grant date | Jun 12, 2007 |
| Priority date | — |
| Expiry date | Feb 23, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M3/496
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A sigma delta analog to digital converter of the type adapted to be connected to a capacitive current input device, comprises: a sigma delta modulator having an input; and a flying capacitor constructed so as to be connected between the input of the sigma delta modulator and the capacitive current input device. In a preferred embodiment, the converter includes an input stage having an input coupled to the flying capacitor; a feedback path; a digital to analog converter (DAC) disposed in the feedback path and having a DAC output; and a DAC output capacitor and a second switch for alternately switching the DAC output capacitor between a first connection so as to transfer a signal from the output of the digital to analog converter to the DAC output capacitor and a second connection so as to transfer a signal from the DAC output capacitor to the input of the sigma delta modulator. The flying capacitor includes a charging capacitor and a flying capacitor switch, the flying capacitor being constructed so as to be alternately switched between a first connection so as to transfer a signal from the capacitive current input device to the charging capacitor and a second connection so as to tr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.