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:
Jul. 03, 2001
Filed:
Feb. 12, 1998
Masahiro Imai, Yamatokoriyama, JP;
Kunihiko Yamamoto, Kashiba, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A driving voltage generating circuit of a matrix-type display device includes a voltage dividing resistor group composed of a plurality of voltage dividing resistors connected in series, for dividing a potential a difference of a reference voltage. It also includes operational amplifiers for generating and outputting row voltages (a selective voltage and a non-selective voltage) to be applied to row electrodes, by subjecting each voltage obtained by voltage division to impedance conversion. A p-channel MOSFET and an n-channel MOSFET as analog switches for altering a level of each voltage thus generated are provided in parallel with voltage dividing resistors at ends of the voltage dividing resistor group. With this arrangement, the number of elements necessary for the circuit, for example, MOSFETS and level shifters for controlling the MOSFETS, can be decreased. Therefore, the size of the driving voltage generating circuit can be reduced. As such, price lowering and reduction of power consumption can be achieved.