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:
Sep. 18, 2001
Filed:
Aug. 23, 2000
Abstract
The invention relates to a circuit arrangement for operating at least one discharge lamp, which has a half-bridge inverter (T,, T,, A) with a downstream load circuit (LD, CR) and has a half-bridge capacitor (CK) and also a monitoring apparatus for monitoring a change in the voltage drop across the half-bridge capacitor (CK) which is caused by the occurrence of a rectifying action in the at least one discharge lamp LP. According to the invention, the monitoring apparatus has a first RC element (R,, C,) and a second RC element (R,, C,), which are connected to one another by a threshold switch (DC), and means for detecting the switching state of the threshold switch (DC). The first RC element (R,, C,) is connected to the center tap of the half-bridge inverter, and the second RC element (R,, C,) is connected to the half-bridge capacitor (CK).