Patent · US Expired

Backlighting circuits including brownout detection circuits responsive to a current through at least one light emitting diode and related methods

US6107985A · kind A · utility

23Cited by
13References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 30, 1997
Grant dateAug 22, 2000
Priority date
Expiry dateOct 30, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2330/12
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A backlighting circuit for user interface in an electronic device includes at least one light emitting diode optically coupled to the user interface wherein the at least one light emitting diode provides backlighting for the user interface. A current source is electrically coupled in series with the at least one light emitting diode wherein the current source controls a current through the at least one diode. In addition, a brownout detection circuit determines a brownout condition for the user interface responsive to the current through the diode. Related communications devices and methods are also discussed.

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