A method of cascading two second-order sigma-delta modulators includes the steps of feeding the input to the quantizer of the first stage to the second stage. This input is, effectively, the difference between the output of the first second-order loop and the quantization noise of the first modulator. The method also includes the step of removing both the quantization noise from the first loop as well as the output from the first loop from a final output, y.sub.out.
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