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:
Sep. 23, 2003
Filed:
May. 22, 2000
Keith A. Tilley, Round Rock, TX (US);
Motorola, Inc., Schaumbschaumburg, IL (US);
Abstract
A DC offset correction method and apparatus. In a differential system, a DC offset correction loop includes a gain stage ( ) having a differential input, a gain G and a differential output. A DAC circuit ( ) provides a correction DC signal at the inputs to produce differential output signals V ′ and {overscore (V )}′. A controller ( ) corrects the DC offset by stepping the DAC circuit ( ) to change the correction DC signal by an amount equal to approximately (V ′−{overscore (V ′)})/G , where G is the gain G times the gain of the DAC expressed in volts per DAC step. A similar algorithm can be applied to single ended systems wherein a single ended V is corrected by an amount equal to approximately V /G .