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:
Dec. 19, 1995
Filed:
Apr. 13, 1994
Hiroshi Suzuki, Yamato, JP;
Midori Suzuki, Machida, JP;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A drive circuit is disclosed for a liquid crystal display apparatus of the active matrix type having a large number of gray levels that can be displayed. The drive circuit comprises a plurality of sections each including a sample-and-hold circuit 22. The sample-and-hold circuit 22 has a plurality of switches Sw 1 through Sw 4. To these switches are separately supplied different ramp signals Vr 1 through Vr 4 from a ramp generator circuit 24 shared by all the sections. These ramp signals have waveforms which respectively assume a plurality of different voltage levels and are shifted from each other by a predetermined voltage level. The decoder 21 selects one of the switches Sw 1 through Sw 4 and a specific one of the voltage levels in the ramp signal applied to that selected switch depending on the gray scale data in the latch 20. The output of the sample-and-hold circuit is transmitted to the data line 7a via a buffer 23.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile