Improved offline calibration for DAC mismatch in low OSR Sigma Delta ADCs with distributed feedback
نویسندگان
چکیده
Improved offline calibration for DAC mismatch in low OSR Sigma Delta ADCs with distributed feedback, " in Proc. Abstract—We present an offline calibration method to correct the non-linearity due to DAC element mismatch in distributed feedback SigmaDelta-modulation A/D-converters. The improvement over previous methods is that not only the first feedback DAC is calibrated, but also the DACs that are coupled to later stages can be calibrated as well. This is needed in the case of Sigma Delta modulators with a low OSR, where the contribution of the second feedback DAC should not be neglected. The technique is based on a calibration measurement with a two-tone input signal.
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