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. 30, 2001
Filed:
Apr. 13, 1999
Tomoaki Nakao, Yamatokoriyama, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A liquid crystal driving circuit includes: a charge capacitor and a distribution capacitor, each having a first electrode and a second electrode, respective first electrodes of the charge capacitor and the distribution capacitor being connected to each other; a first switch for connecting and disconnecting respective second electrodes of the charge capacitor and the distribution capacitor; a select switch for selecting application of a first reference voltage and a second reference voltage with respect to the second electrode of the charge capacitor by connection or disconnection; an operational amplifier for outputting an analog signal for multi-tone display in accordance with an amount of charge of the distribution capacitor and the second reference voltage; and a controller for alternately controlling the first switch and the select switch in accordance with a digital signal for multi-tone display.