Parallel-tuned electronic ballast

  • US 5,189,342 A
  • Filed: 02/25/1992
  • Issued: 02/23/1993
  • Est. Priority Date: 10/05/1984
  • Status: Expired due to Term
First Claim
Patent Images

1. A ballast for a gas discharge lamp, comprising:

  • a source operative, between a first and a second DC output terminal, to provide a DC voltage of substantially constant magnitude; and

    inverter-type power supply connected with the DC output terminals and operative to provide a high-frequency AC voltage between a first inverter output terminal and an inverter reference terminal;

    the high-frequency AC voltage being of a certain magnitude and a certain frequency;

    the certain frequency being substantially higher than the frequency of the power line voltage on an ordinary electric utility power line;

    the power supply including a tuned L-C circuit connected with the first inverter output terminal and the inverter reference terminal;

    the L-C circuit having a tank capacitor parallel-connected with a tank inductor and being resonant at or near said certain frequency;

    any high-frequency voltage existing between the inverter reference terminal and the first DC output terminal being of magnitude negligible in comparison with said certain magnitude.

View all claims

    Thank you for your feedback