Battery feed circuit for a pair of subscriber lines
US4677669A · kind A · utility
13Cited by
1References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 23, 1985 |
| Grant date | Jun 30, 1987 |
| Priority date | — |
| Expiry date | May 23, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M19/005
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Battery feed circuit for a pair of subscriber lines includes a voltage drive circuit with an operational amplifier having a predetermined output impedance determined by an alternating current terminal impedance for the pair of subscriber lines. Both voice signals and induced noise signals are terminated by the voltage drive circuit. The voltage drive circuit is connected in parallel with an electronic inductance circuit, between one of the subscriber lines and ground or a direct current voltage supply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.