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. 11, 2010
Filed:
Nov. 12, 2008
Shui-mu Lin, Longjing Township, Taichung County, TW;
Tsung-wei Huang, Jubei, TW;
Jien-sheng Chen, Toufen Township, Miaoli County, TW;
Kwan-jen Chu, Hsinchu, TW;
Shui-Mu Lin, Longjing Township, Taichung County, TW;
Tsung-Wei Huang, Jubei, TW;
Jien-Sheng Chen, Toufen Township, Miaoli County, TW;
Kwan-Jen Chu, Hsinchu, TW;
Richtek Technology Corp., Hsinchu, TW;
Abstract
A single-ended operational amplifier includes an output stage, a first transconductance amplifier and a second transconductance amplifier. In an offset cancellation mode, two inputs of the first transconductance amplifier are supplied with a reference voltage to sink two currents from two inputs of the output stage respectively, the output stage generates a third current according to the difference between the two currents to charge a capacitor, and the second transconductance amplifier generates two currents according to the voltage in the capacitor to make currents in the two inputs of the output stage equal to each other, thereby canceling the offset of the single-ended operational amplifier.