Telephone line overvoltage protection apparatus
US5359657A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 9, 1993 |
| Grant date | Oct 25, 1994 |
| Priority date | — |
| Expiry date | Jun 9, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H9/044
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An overvoltage protection apparatus used with a pair of telephone lines includes first voltage clamping circuitry for clamping voltage signals on the lines at a first predetermined voltage potential. The first voltage clamping circuitry is formed by at least a pair of solid-state protective chip devices and a failure mode mechanism adapted for connecting the lines to ground responsive to increased temperature of the solid-state protective chip device and providing a ground connection for the pair of solid-state protective chip devices. A pair of current limiting resistors operatively connected to the failure mode mechanism provide sneak current protection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.