Radio communications devices with backlighting circuits having brownout detection circuits responsive to a current through a light emitting diode
US6256007A · kind A · utility
13Cited by
19References
22Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 11, 2000 |
| Grant date | Jul 3, 2001 |
| Priority date | — |
| Expiry date | May 11, 2020 |
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.