Telephone system with current regulation in the constant current region
US6980648B2 · kind B2 · utility
0Cited by
5References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 14, 2002 |
| Grant date | Dec 27, 2005 |
| Priority date | — |
| Expiry date | Jul 2, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M19/005
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephone system includes a transmission line for connection to at least one telephone and a telephone interface in communication with the transmission line. The telephone interface provides DC power when a telephone connected to the transmission line is in an off-hook state. A controller in communication with the telephone interface generates a pre-defined DC characteristic of the telephone interface, and a regulator in communication with the controller adaptively translates the DC characteristic.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.