Overvoltage protection circuit
US5568345A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 1994 |
| Grant date | Oct 22, 1996 |
| Priority date | — |
| Expiry date | Oct 18, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H9/041
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An overvoltage protection circuit employs a series of semiconductor switching elements, each element having a control terminal and two main conduction terminals, in a totem pole configuration and two potential dividers whose tapping points feed, respectively, the control terminals and the main terminal junctions of the switching elements. Both the series of switching elements and the two potential dividers are connected between a reference node (zero volts) and a node to be protected from an electrostatic discharge. The resistive elements of the potential dividers are so arranged that, in the absence of a static discharge, all switching elements are cut off and experience a substantially equal voltage across the respective main terminals. In this way, the circuit may be usefully employed in integrated circuits which are based on a low-voltage integration process but which have also a high-voltage-supply rail (e.g. 30 V). The switching elements may be bipolar transistors, and preferably Darlington pairs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.