Patent · US Active

Failure detection for series of electrical loads

US8044667B2 · kind B2 · utility

4Cited by
3References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 20, 2009
Grant dateOct 25, 2011
Priority date
Expiry dateMay 20, 2030

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B45/54
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An apparatus for detecting failures in an illumination device includes at least two light emitting diodes connected in series. The apparatus includes a first, a second, and a third circuit node for interfacing the illumination device such that the voltage drop across at least two light emitting diodes is applied between the first and the second circuit node and a fraction of the voltage drop is applied between the second and the third circuit node. An evaluation unit is coupled to the first, the second, and the third circuit node and configured to assess whether the electric potential present at the third circuit node is within a pre-defined range of tolerance about a nominal value that is defined as a pre-defined fraction of the potential difference present between the first and the second circuit node.

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