Patents Represented by Attorney, Agent or Law Firm Randi L. Dalaney
  • Patent number: 6625232
    Abstract: A DC offset correction method and apparatus. In a differential system, a DC offset correction loop includes a gain stage (104) having a differential input, a gain G and a differential output. A DAC circuit (130) provides a correction DC signal at the inputs to produce differential output signals Vo′ and {overscore (Vo)}′. A controller (120) corrects the DC offset by stepping the DAC circuit (130) to change the correction DC signal by an amount equal to approximately (Vo′−{overscore (Vo′)})/Gx, where GX 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 VOFFSET is corrected by an amount equal to approximately VOFFSET/Gx.
    Type: Grant
    Filed: May 22, 2000
    Date of Patent: September 23, 2003
    Assignee: Motorola, Inc.
    Inventor: Keith A. Tilley