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:
Apr. 13, 2010
Filed:
Apr. 05, 2007
Qinghong Yu, Salem, MA (US);
Joseph L. Parisella, Beverly, MA (US);
Qinghong Yu, Salem, MA (US);
Joseph L. Parisella, Beverly, MA (US);
Osram Sylvania Inc., Danvers, MA (US);
Abstract
A circuit () for powering a halogen lamp () comprises an inverter () and an output circuit (). During operation, the inverter () and output circuit () provide a magnitude-limited current to the halogen lamp such that the lamp power during an initial period is substantially less than the lamp power during a steady-state operating period. Preferably, output circuit () is a non-isolated circuit that includes a current-limiting inductance, and inverter () includes a frequency control circuit (R,C,C,Q,R,R,C) for operating the inverter at a higher frequency during the initial period so as to reduce stress upon the lamp filament and preserve the operating life of the lamp. The circuit () is especially suitable for powering low voltage halogen lamps.