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:
May. 01, 1990
Filed:
Apr. 26, 1988
Andrzej Kozicki, Milan, IL (US);
Leo C Brower, Davenport, IA (US);
Uticor Technology, Inc., Bettendorf, IA (US);
Abstract
A voltage regulator circuit provides an economical approach for maintaining the RMS filament voltage of vacuum fluorescent tubes within an acceptable voltage range during input supply voltage variations. The regulator circuit includes substantially identical upper and lower clipper circuits which clip the AC voltage of a step-down transformer secondary. The supply voltage is allowed to vary so that the secondary voltage is outside of the acceptable range of voltage defined by substantially identical voltage reference circuits. Each of the voltage reference circuits is coupled to its respective clipper circuit and to the center tap of the secondary winding of the transformer so that the regulator circuit and the clipped output voltage are symmetrical about the center tap. Th regulator circuit is simple and power-efficient while keeping the filament voltage within the acceptable range of voltages.