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Estimating Non-Ideal Effects within a Top-Down Methodology for the Design of Continuous-Time Delta-Sigma Modulators

  • Received : 2015.10.22
  • Accepted : 2016.02.11
  • Published : 2016.06.30

Abstract

High-level design aids are mandatory for design of a continuous-time delta-sigma modulator (CTDSM). This paper proposes a top-down methodology design to generate a noise transfer function (NTF) which is compensated for excess loop delay (ELD). This method is applicable to low pass loop-filter topologies. Non-ideal effects including ELD, integrator scaling issue, finite op-amp performance, clock jitter and DAC inaccuracies are explicitly represented in a behavioral simulation of a CTDSM. Mathematical modeling using MATLAB is supplemented with circuit-level simulation using Verilog-A blocks. Behavioral simulation and circuit-level simulation using Verilog-A blocks are used to validate our approach.

Keywords

References

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