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. 08, 2015
Filed:
May. 27, 2013
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Abstract
A lighting device includes a switching regulator having an inductor and a switching device, and a controller. The controller includes a peak current detector that outputs a peak detection signal when detecting that a current flowing through the switching device reaches a threshold, a zero-cross detector that outputs a zero-cross detection signal when a current discharged from the inductor reaches a predetermined lower limit value or less, a synchronization signal controller that outputs a periodic synchronization signal, and a switching controller. The switching controller turns on the switching device in synchronization with a start of an on-period of the synchronization signal and the zero-cross detection signal, and turns off the switching device in synchronization with the peak detection signal. The peak current detector reduces the threshold when an on-period of the synchronization signal finishes, and increases the threshold to an original value when an on-period of the synchronization signal starts.