Electronic ballast
AssigneeLutron Electronics Co., Inc.
InventorsRobert Newman, Stuart DeJonge, Mark Taipale, Dominick Travaglini, Joel Spira
Life of this patent
Estimating the term…
Abstract
An electronic ballast for driving at least one lamp comprising a rectifying circuit operatively connectable to an AC line; a current drawing circuit connected across said rectifying circuit; and an inverter circuit connected to said rectifying circuit that supplies a lamp current to said at least one lamp; wherein said current drawing circuit draws current from said AC line when the instantaneous voltage of said AC line nears zero to reduce the total harmonic distortion of the input current drawn by said ballast.
Claims17
1-6. (canceled)
An electronic ballast for driving at least one lamp comprising:
- a rectifying circuit operatively connectable to an AC line for providing a rectified voltage;
- a current drawing circuit connected across said rectifying circuit;
- said current drawing circuit drawing current from said AC line only when the instantaneous voltage of said AC line nears zero to reduce the total harmonic distortion of the input current drawn by said ballast;
- and
- an inverter circuit connected to said rectifying circuit that supplies a lamp current to said at least one lamp.
An electronic ballast for driving at least one lamp comprising:
- a rectifying circuit operatively connectable to an AC line;
- a valley fill circuit including a capacitor;
- said valley fill circuit operable to selectively charge said capacitor directly from said AC line through said rectifying circuit, an impedance, and a first electronic switching device;
- and
- an inverter circuit including at least one electronic switching device for supplying lamp current to said at least one lamp;
- wherein said capacitor is charged during at least 90° of each half-cycle of said AC line.
An electronic ballast for driving at least one lamp comprising:
- a rectifying circuit operatively connectable to an AC line;
- a valley fill circuit including an energy storage device;
- said valley fill circuit operable to selectively charge said energy storage device;
- a back end which includes an inverter circuit that supplies a lamp current to said at least one lamp;
- a control circuit for controlling the operation of said inverter circuit;
- and
- a cat ear circuit that supplies power to said control circuit;
- wherein said inverter circuit draws a first current from said AC line during a first predetermined portion of each half cycle which is greater than 90° of each half cycle of said AC line and said cat ear circuit draws a second current from said AC line during a second predetermined portion of each half cycle which is less than 90° of each half cycle of said AC line
An electronic ballast for driving at least one lamp comprising:
- a rectifying circuit operatively connectable to an AC line;
- a valley fill circuit including an energy storage device;
- said valley fill circuit operable to selectively charge said energy storage device directly from said AC line through said rectifying circuit, an impedance, and a first controllably conductive switch.
Dependencies are inferred from the claim text.