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:
Nov. 19, 1996
Filed:
Dec. 19, 1994
Shingo Isozaki, Suwa, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
The objectives of this invention are to improve the method of supplying power from an operating power source and thus implement a liquid crystal drive device with an internal display data storage device that consumes less power and is also larger. A signal electrode drive circuit (X driver) is made up of a low-voltage-amplitude operating portion that operates on the supply of a first power voltage group, and a high-voltage-amplitude operating portion that operates on the supply of a second power voltage group. A frame memory that stores display data is provided in the high-voltage-amplitude operating portion, with the configuration being such that the operating power source for the frame memory is supplied from the second power voltage group. The power source of the frame memory could also be supplied through a constant-voltage circuit that regulates these second power voltages, and the supply of the first and second power voltages could be switched in accordance with the state of the second power voltage supply by a power monitoring device that monitors the second power voltage group. The configuration of the present invention is particularly effective for the multiple line selection drive method.