PARALLEL TRANSFORMER WITH OUTPUT SIDE ELECTRICAL DECOUPLING
First Claim
1. A ballast circuit comprising:
- at least first and second lamps disposed in parallel relation;
first and second secondary windings of first and second transformers, respectively, disposed in parallel for providing power to the first and second lamps, respectively; and
an electrical decoupling assembly that electrically decouples the first and second secondary windings of the transformers after a preheat phase of lamp ignition is complete.
1 Assignment
0 Petitions
Accused Products
Abstract
A higher power package is provided in a smaller package by providing at least first and second magnetics in parallel in first and second transformers. To limit degrading performance associated with circulating current between the two transformers, the transformers are electrically decoupled. In a preferred embodiment, the circuit includes parallel primary and secondary windings of the transformer that are decoupled electrically on an output side. Particularly, diodes are provided in a preheat portion of the circuit so that once the preheat phase is terminated, the diodes prevent current flow in one direction through the preheat portion of the circuit.
7 Citations
18 Claims
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1. A ballast circuit comprising:
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at least first and second lamps disposed in parallel relation; first and second secondary windings of first and second transformers, respectively, disposed in parallel for providing power to the first and second lamps, respectively; and an electrical decoupling assembly that electrically decouples the first and second secondary windings of the transformers after a preheat phase of lamp ignition is complete. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A method of improving lamp performance in a multi-transformer lamp ballast circuit comprising:
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providing first and second transformers; and electrically decoupling the first and second transformers after a preheat phase of operation has been completed. - View Dependent Claims (13, 14, 15, 16, 17, 18)
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Specification