Patent · US Active

Combined ballast for fluorescent lamp and light emitting diode and method of driving same

US7759880B2 · kind B2 · utility

4Cited by
2References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 12, 2008
Grant dateJul 20, 2010
Priority date
Expiry dateDec 5, 2028

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J61/327
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A circuit or combined ballast for driving a fluorescent lamp and at least one light emitting diode (LED) includes an integrated driver circuit having an alternating current (AC) circuit that includes at least one ballast coil for driving the fluorescent lamp and a direct current circuit for driving the LED having a secondary winding inductively coupled with the fluorescent lamp ballast coil for driving the LED. A method of driving a lamp assembly includes at least one fluorescent lamp and at least one light emitting diode (LED) and a combined driver circuit for supplying both the fluorescent lamp and the LED. The combined driver circuit supplies high voltage AC supply to a first portion of the driver circuit to the fluorescent lamp, supplies low voltage DC supply in a second portion of the driver circuit to the LED, and provides a secondary winding in the second portion of the driver circuit that is inductively coupled with a ballast coil in the first portion of the driver circuit that drives the fluorescent lamp.

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