The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 14, 2000
Filed:
Jul. 25, 1997
Mihail S Moisin, Brookline, MA (US);
Pacific Scientific, Washington, DC (US);
Abstract
A dimmable electronic ballast for a gas discharge lamp utilizing a modified self-resonant split inductor configuration. The voltage supplied to the lamp load is controlled by varying the duty cycle of the output stage which, in turn, feeds back a driving signal to the boost converter to synchronize the DC voltage with the needs of the load. The circuit also performs power factor and THD control. The ballast circuit controls the start-up of the lamp by proving a warming current to the filaments and then boosts the voltage to strike the lamps. If the lamps are at end-of-life wherein the filaments are intact but vapor and coatings are diminished, the ballast will apply bursts of higher voltage until the lamp strikes. Additionally, if the filaments are open, the circuit stops operation.