Systematic Design of Double-sampling Σ∆ Adc’s with Modified Ntf
نویسندگان
چکیده
A disadvantage of double-samplingΣ∆ ADC’s is their sensitivity to path mismatch. Recently, an approach to solve this problem was presented. It consists of modifying the noise transfer function (NTF) of the modulator such that it has a zero at the Nyquist frequency, next to those in the baseband. Unfortunately, no systematic design strategy for such ADC’s is available. In this work, we present such a strategy. It consists of finding optimal pole positions for the modified NTF. This can be combined with optimizing the zeros of the NTF. Next, we introduce a novel efficient structure that has enough flexibility to realize the optimized pole positions.
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