Lower power reference for an analog to digital converter
US10826519B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2019 |
| Grant date | Nov 3, 2020 |
| Priority date | — |
| Expiry date | Aug 27, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/16
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The present disclosure provides alternative solutions to the problem of providing a stable voltage reference to high speed ADCs that possess high sampling rates. In one example the high speed amplifier is replaced by a smaller, slower, lower power amplifier in combination with a relatively large capacitor connected to the same node as the amplifier output and the ADC reference input. The capacitor is charged substantially to the external reference voltage and hence keeps the reference input of the ADC almost at the external reference voltage between conversions, such that when conversion is about to occur and the external reference is switched in then very little charge is required from the external reference, and hence the reference signal quickly settles. An alternative arrangement is to replace the amplifier with a comparator that takes as one of its inputs the external reference signal, and as the other of its inputs the internal reference to the ADC, and makes use of a control circuit that adjusts the threshold of the comparator from bit-trial to bit-trial until the internal reference is brought up to substantially the same signal level as the external reference. When the exte…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.