D/A converting device with offset compensation function and offset compensation method of D/A converting device
US6888481B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 7, 2004 |
| Grant date | May 3, 2005 |
| Priority date | — |
| Expiry date | Jan 7, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/66
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An input changing switch is provided at a preceding stage of a comparator that measures a DC offset of a D/A converter, and also a selective polarity inverting circuit is provided at a subsequent stage. A first compensation value is generated by a compensation value generating means and then stored in a register. Then, a second compensation value is generated by switching the input changing switch and the polarity inverting circuit and then stored in a register. Then, a third compensation value is calculated by averaging the first compensation value and the second compensation value by a compensation value calculating circuit. Then, the DC offset of the D/A converter is compensated by using this compensation value. Therefore, it enables to implement a precise DC offset compensation of the D/A converter by canceling the DC offset contained in the comparator itself employed in the DC offset compensation of the D/A converter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.