Method and apparatus for calculating DC offset in a digital gyrator
US6553118B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 1999 |
| Grant date | Apr 22, 2003 |
| Priority date | — |
| Expiry date | Aug 20, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M19/001
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for controlling the DC line current on a telephone line and reducing the amount of error introduced to the system. The error is reduced by compensating for a DC error term introduced by an analog to digital converter having a DC offset. The DC offset is controlled digitally, allowing software to be used to limit the DC error in accordance with predefined parameters. Predefined parameters can be set to accommodate varying country specifications instead of using switches to control resistors and capacitors. In addition, changes in a country's requirements can be accomplished through software, instead of changing components or redesigning a circuit board. The use of software results in increased flexibility by allowing an infinite number of settings via software or software updates, allowing changes to be made quickly and easily throughout the world, and allowing error terms to be accommodated digitally.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.