Telephone and communications line overvoltage protection apparatus
US5677820A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 18, 1996 |
| Grant date | Oct 14, 1997 |
| Priority date | — |
| Expiry date | Jul 18, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/18
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An overvoltage protection apparatus is used with a pair of telephone or communications TIP/A and RING/B lines including voltage clamping circuitry for clamping voltage signals on the lines at a predetermined voltage potential. The voltage clamping circuitry includes a pair of voltage clamping devices connected in series between the TIP/A and RING/B lines and a third voltage clamping device connected between a junction connection of the pair of the voltage clamping devices and a ground potential connection and current limiting devices for limiting current flow in the lines. The predetermined voltage potential exceeds a primary alternating current (AC) power line peak value by a set tolerance value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.