DC offset calibration of ADC with alternate comparators
US9496884B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 2016 |
| Grant date | Nov 15, 2016 |
| Priority date | — |
| Expiry date | Mar 21, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/361
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
System and method of calibrating the DC offsets of alternate comparators in an ADC in the background based on the digital outputs of the ADC. In parallel with A/D conversion of a plurality of samples, the calibration logic uses two counters to count the occurrences of the ADC outputs that represent samples falling in a first analog range and a second analog range, respectively. The two ranges are symmetric about the MSB reference voltage and in combination cover the nominal voltage range of the bit. The DC offset is derived based on a ratio of the difference between the two counts and a sum of the two counts. The calibration logic may alternately calibrate the comparators. Each comparator may be calibrated successively based on various bits associated therewith.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.