An anti-aliasing filter inspired by continuous-time ΔΣ modulation
نویسندگان
چکیده
An anti-aliasing filter that incorporates a sampler is proposed to precede noise-shaping analog-to-digital converters (ADCs), such as discrete-time ΔΣ modulators. The architecture of the proposed anti-aliasing filter is inspired by the implicit antialiasing filtering property of CT ΔΣ modulators. However, contrary to CT ΔΣ modulators, the proposed anti-aliasing filter is not sensitive to clock jitter. Furthermore, its key characteristics include: 1) higher suppression of aliases, compared to a Butterworth filter of the same order (same number of opamps); and 2) high-pass shaping of the sampling errors. Its performance advantages are derived theoretically and then confirmed through behavioural simulations.
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