Transient protection circuit using common drain field effect transistors
US5198957A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 1990 |
| Grant date | Mar 30, 1993 |
| Priority date | — |
| Expiry date | Jul 2, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/18
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A transient protection circuit provides protection from high voltage transients appearing along a transmission line by sensing a predetermined threshold of the voltage developed thereon and opening the conduction path through first and second switching circuits in the transmission line. The switching circuits are implemented with first and second serially coupled transistors sharing a common drain and enabled by a control signal during normal operation. The first and second transistors each have a diode oriented to conduct from the source to the drain for bi-directional operation. During high voltage transient conditions, a sensing circuit detect a predetermined threshold of the potential on the transmission line and disables one of the first and second transistors which opens the conduction path through the first and second switching circuits thereby suppressing the surge currents flowing therethrough.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.