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:
Apr. 25, 2006
Filed:
Nov. 14, 2002
Hiroshi Nakatsuka, Katano, JP;
Katsu Takeda, Osaka, JP;
Takashi Ishikawa, Daito, JP;
Katsunori Moritoki, Takatsuki, JP;
Hiroshi Nakatsuka, Katano, JP;
Katsu Takeda, Osaka, JP;
Takashi Ishikawa, Daito, JP;
Katsunori Moritoki, Takatsuki, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A driving circuit for a piezoelectric transformer is provided, which is capable of driving a piezoelectric transformer at a high efficiency and with low distortion, and being miniaturized. At the commencement of lighting a cold-cathode fluorescent tube, a digital controller fixes frequencies of first and second control signals VCand VCat a predetermined frequency and controls the phase difference therebetween so that an output power of the piezoelectric transformer becomes from substantially zero to a predetermined output power. After lighting of the cold-cathode fluorescent tube, the digital controller controls the phase difference between the first and second control signals VCand VCso that current detecting data CD substantially is matched with reference data RD.