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:
Nov. 09, 1999
Filed:
Apr. 17, 1998
Applicant:
Inventors:
Jerzy Janczak, Woodhaven, NY (US);
Pawel M Gradzki, Potomac, MD (US);
Assignee:
Philips Electronics North America Corporation, New York, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G05F / ; H05B / ;
U.S. Cl.
CPC ...
323282 ; 323908 ; 315247 ;
Abstract
A dimmable fluorescent lamp including a feedback circuit for drawing sufficient current to maintain an appropriate charge across the buffer capacitor. A bypass capacitor provides a path for diverting a portion of the power which would otherwise be fed back to the buffer capacitor during low level dimming. Consequently, overboost voltages across the buffer capacitor during low level dimming are substantially reduced.