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:
Feb. 26, 2002
Filed:
Jan. 19, 2000
Applicant:
Inventors:
Berthold Birk, Aschaffenburg, DE;
Günter Hahlganss, Kriftel, DE;
Walter Kares, Frankfurt, DE;
Ulrich Roskoni, Wöllstadt, DE;
Assignee:
Mannesmann VDO AG, Frankfurt, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H05B 3/702 ;
U.S. Cl.
CPC ...
H05B 3/702 ;
Abstract
In a circuit arrangement for the dimmable operation of a fluorescent lamp at the operating frequency (f ), having an apparatus for switching the operating frequency (f ) on and off at a dimming frequency (f ), the pulse width (W ) of the dimming frequency (f ) being variable, and where f <f it is provided that the fluorescent lamp current is simultaneously adjustable by the apparatus by the supply voltage being switched on and off at a switching frequency (f ) with a variable pulse width (W ), where f >f