| 摘要 |
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.
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