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:
Jan. 01, 2013
Filed:
Mar. 06, 2008
Wei Gao, Guangzhou, CN;
Wei Gao, Guangzhou, CN;
Osram Gesellschaft Mit Beschraenkter Haftung, Munich, DE;
Abstract
A method of driving regulation for bipolar transistors in electronic ballast is provided. The method may include: sensing voltage at midpoint of half bridge of the transistors; producing a reference time signal according to a sync signal from a timer; producing actual time interval in this cycle by comparing rising edge of the voltage at midpoint of the half bridge of the transistors with rising edge of a driving signal for the transistors in upper bridge arm in each switching cycle; comparing the actual time interval with the reference time signal to determine pulse width of the driving signal; regulating, in which the driving signal in this switching cycle is prolonged relative to the driving signal in previous switching cycle if the actual time interval is larger than the reference time signal, while the driving signal in this switching cycle is shortened relative to the driving signal in previous switching cycle if the actual time interval is smaller than the reference time signal.