×

Modular, configurable dimming ballast for a gas-discharge lamp

  • US 6,107,755 A
  • Filed: 04/27/1998
  • Issued: 08/22/2000
  • Est. Priority Date: 04/27/1998
  • Status: Expired due to Fees
First Claim
Patent Images

1. An electronic ballast for exciting a gas-discharge lamp to produce a varying light output level related to a variable lamp current provided thereto, comprising:

  • a) a ballast circuit for providing a variable output lamp current responsive to an input signal;

    b) lamp current monitoring means operatively connected to said ballast circuit for producing a lamp current signal representative of said lamp current;

    c) a first feedback path between said ballast circuit and said lamp current monitoring means operable primarily when said lamp current is within a first, predetermined range of lamp current values;

    d) a second, parallel feedback path between said ballast circuit and said lamp current monitoring means operable primarily when said lamp current is within a second, predetermined range of lamp current values; and

    e) means for generating a control signal operatively connected to said ballast circuit and operating cooperatively with said first feedback and said second feedback path to set a specific output lamp current value and a specific light output level related thereto, by providing said input signal to said ballast circuit;

    whereby said specific output lamp current and said related specific light output level is maintained at a substantially constant level.

View all claims
  • 6 Assignments
Timeline View
Assignment View
    ×
    ×