Patent · US Active

Protection circuit and method

US7884557B2 · kind B2 · utility

8Cited by
7References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 10, 2007
Grant dateFeb 8, 2011
Priority date
Expiry dateSep 7, 2029

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B20/30
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A light source is protected by selectively coupling a shunt path in parallel with the light source, such that current is diverted away from the light source and through the shunt path. A detection circuit detects the current flowing in the shunt path when the shunt path is connected in parallel with the light source. A comparator determines whether the current flowing in the shunt path exceeds a predetermined threshold and, if so, prevents or limits the flow of current when the shunt path is disconnected from being in parallel with the light source. In this way, a current detector is provided for monitoring the flow of current in a shunt path, the current detector being configured to disable or limit the flow of current through a light source when a predetermined threshold is reached. This aspect of the invention has the advantage of enabling the current flowing through a light source to be controlled by monitoring the current in the shunt path rather than the path having the light source, thus enabling the maximum current to be controlled without potentially damaging the light source.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.