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:
Oct. 09, 1990
Filed:
Jun. 26, 1989
Yosihide Fujioka, Nara, JP;
Yoshiharu Kanatani, Nara, JP;
Toshihiro Ohba, Nara, JP;
Hisashi Uede, Wakayama, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A thin film electroluminescent (EL) display panel drive circuit includes first and second switching circuits for driving scanning electrodes of the panel in two fields, wherein odd numbered scanning electrodes are applied with a negative voltage polarity and even numbered scanning electrodes are provided with a positive voltage polarity in a first field, and the voltage polarities are reversed during the second field. Data signals are applied to data electrodes by a data electrode driver circuit which includes third and fourth switching circuits for providing selected data electrodes with a modulate voltage of a stepwise nature or ground, depending upon whether the selected data electrodes intersect with selected scanning electrodes having a negative or positive voltage polarity respectively. The stepwise modulation voltage is supplied by a control switching circuit which selectively supplies the third switching circuit with voltages of a first level, a second level and a floating level.