Apparatus for protecting against overvoltage
US5164874A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 13, 1991 |
| Grant date | Nov 17, 1992 |
| Priority date | — |
| Expiry date | Mar 13, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus for protecting against overvoltage includes a semiconductor switching element and a trigger element. The semiconductor switching element is formed of a PNPN junction including a plurality of PN junctions and the trigger element has a characteristic similar to that of a PN junction Zener diode. The apparatus for protecting against overvoltage is normally nonconductive; however, once an overvoltage not lower than a defined level is applied, the trigger element attains a state so as to have a gate current flow from a gate electrode thereof to the semiconductor switching element. In response to this, the semiconductor switching element causes a so-called thyristor phenomenon, thereby protecting a load connected in parallel to the apparatus for protecting against overvoltage, i.e., an object to be protected, from being provided with the overvoltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.