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. 06, 1997
Filed:
Jul. 18, 1994
Hisanobu Ishiyama, Suwa, JP;
Shigeki Aoki, Suwa, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
An objective of the present invention is to provide a power supply device, a liquid crystal display device, and a method of supplying power that can enable designs with lower power consumptions and can also enable higher display qualities. A first voltage Vx, which is a constant voltage, is generated by a first voltage generation portion in a voltage regulation portion. A second voltage Vy having a value independent of that of Vx is generated by a second voltage generation portion, and Vx and Vy are added by an adder portion to generate a regulated voltage Vreg. A control portion provides variable control of Vy within a voltage regulation range that is defined to include Vx. The regulated voltage Vreg is divided by a voltage divider portion within a multi-value voltage generation portion. The impedances of voltages V2 and V4 are converted by first impedance conversion portions (n-type OP-amps), and the impedances of voltages V1 and V3 are converted by second impedance conversion portions (p-type OP-amps).