CONTINUOUS-TIME SIGMA-DELTA ANALOG-TO-DIGITAL CONVERTER WITH NON-INVASIVE FILTER(S) FOR IMMUNITY PRESERVATION AGAINST INTERFERERS.

摘要

A continuous-time sigma-delta analog-to-digital converter (CV) comprises i) a signal path (SP) which includes at least one combiner (C1) for combining analog signals to be converted with analog feedback signals, at least one integrator (H1) for integrating the combined analog signals, a quantizer (Q) for converting the integrated signals into digital signals, and ii) a feedback path (FP) comprising at least a digital-to-analog converter (DAC) for converting the digital signals outputted by the quantizer (Q) into analog feedback signals intended for the combiner (C1). It also comprises at least one non-invasive filter (N1) associated to the integrator (H1), connected in parallel to the signal path (SP) at a chosen location and arranged to introduce a notch into its signal transfer function by suppressing unwanted analog interference signals having a chosen frequency band that corresponds to this notch.