Inductively coupled ballast circuit

  • US 7,180,248 B2
  • Filed: 10/22/2004
  • Issued: 02/20/2007
  • Est. Priority Date: 06/21/1999
  • Status: Active Grant
  • ×
    • Pin Icon | RPX Insight
    • Pin
First Claim
Patent Images

1. A ballast circuit comprising:

  • an electromagnetic radiation emitting assembly comprising a secondary coil electrically connected with an electromagnetic radiation emitting device;

    a tank circuit comprising an inductive coupler, said inductive coupler having a primary coil, said inductive coupler and said secondary coil operable to form a transformer to inductively couple said electromagnetic radiation emitting assembly and said tank circuit, said secondary coil and said inductive coupler forming a coupling coefficient, an operating point of said electromagnetic radiation emitting device being adjustable as a function of said coupling coefficient;

    a switching circuit;

    a driver electrically connected with said switching circuit; and

    an oscillator electrically connected with said driver and said tank circuit, said oscillator operable to energize said tank circuit as a function of feedback from said tank circuit, said tank circuit operable to inductively energize said electromagnetic radiation emitting device, wherein said ballast circuit is operable to self oscillate to maintain resonate frequency as a function of reflected impedance of said electromagnetic radiation emitting assembly.

View all claims

    Thank you for your feedback