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:
May. 09, 2000
Filed:
Nov. 13, 1998
Sadashi Shimoda, Chiba, JP;
Seiko Instruments Inc., , JP;
Abstract
A power supply circuit for supplying power which may be used to drive a liquid crystal display unit in a multiline addressing scheme, in which drive voltages VH, VL and Vi on the common side of the liquid crystal display unit can satisfy the relationship VH-Vi=Vi-Vt with high accuracy, comprises a switching regulator for generating a first output voltage of a first polarity, a resistor connected to the first switching regulator to divide the first output voltage and produce a divided output voltage, and a second, constant-voltage power supply circuit which includes an error amplifier that inputs the divided output voltage as one of a supply voltage and a reference voltage and which generates a second output voltage opposite in polarity to the first polarity so that a constant relationship is maintained between the first and second output voltages.