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:
Aug. 03, 2004
Filed:
Jun. 27, 2002
Chin-Hui Wang, Taipei, TW;
Liang-Pin Tai, Tainan Hsien, TW;
RichTek Technology Corp., Hsinchu, TW;
Abstract
A voltage reference circuit includes a current source unit, a voltage-difference creating unit, and a resistance ratio unit. The current source unit receives an input current source and produces two current sources in equal current. The voltage-difference creating unit includes a first MOS device and a second MOS device to respectively receive the two current sources, wherein the first MOS device and a second MOS device has a threshold voltage difference. The resistance ratio unit includes a first resistor and a second resistor coupled in cascade, wherein the threshold voltage difference is applied to the first resistor. By adjusting a ratio of the first resistor to the second resistor, the resistance ratio unit produces a voltage reference, which is also fed back to the current source unit to ensure that the first current source and the second current source are equal.