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:
Jun. 10, 1986
Filed:
Jul. 23, 1984
U.S. Philips Corporation, New York, NY (US);
Abstract
A circuit arrangement for operating high-pressure gas discharge lamps (6) with a current of higher frequency comprising a switching mains section including a switching transistor (4) and a control device (9), in which an upper and a lower reference current level (O,U) are produced. The switching transistor is switched to the non-conducting state when the lamp current exceeds the upper level (O) and is switched to the conducting state when this current falls below the lower level (U). The interval between the reference current levels (O,U) is more than 10% of the average lamp current and a further intermediate reference current level (M) is provided at which the switching transistor is switched each time at a predetermined number of passages of the lamp current through the intermediate reference current level.