Digital signal transmitting circuit for telephone network
US4805214A · kind A · utility
6Cited by
3References
2Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 13, 1987 |
| Grant date | Feb 14, 1989 |
| Priority date | — |
| Expiry date | Nov 13, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q2213/1332
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A circuit is disclosed for the transmission of digital signals on a bifilary line, especially a telephone line. The circuit disclosed is a so-called S interface circuit which has to produce digital signals within certain set limits. The proposed circuit uses four differential amplifiers, each controlling an output transistor (N-channel MOS transistors and P-channel MOS transistors). The amplifiers receive feedback to maintain the overvoltages within acceptable limits. The invention applies especially to the setting up of integrated service digital telephone networks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.