Modeling charge injection non-linear effects in Sigma-Delta Modulators using SIMULINK |
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| Alberto Dei, Maurizio Valle |
- Abstract:
- Sigma-delta (ΣΔ) modulators are the most suitable A/D converters for low to medium frequencies, high-resolution applications, in view of their inherent linearity, reduced antialiasing filtering requirements and robust analog implementation. Moreover, the growing market for asymmetrical digital subscriber line (ADSL) applications is a driving force for the development of high speed, high resolution, sigma-delta analog-to-digital converters (ADC’s). In the wider development of ADC systems, a pre-eminent role has been played by modeling techniques. Modeling of ADC allows the device behavior to be predicted with a few of preventive experiments. For this reason, in the last years a great deal of scientific interest has been directed to ADC modeling.
In this work we present a SIMULINK model, which takes into account, for the first time, the non-linear effects due to switch charge injection in Sigma-Delta modulators. These effects are non-linearly proportional to the input voltage value. This brings about offset and harmonic distortion. Therefore adequate modeling of charge injection in terms of harmonic distortion is extremely important to predict and estimate the performance of Sigma-delta modulators. - Keywords:
- Charge injection modeling, Sigma-Delta converters, Switched-capacitor integrators
- Download:
- IMEKO-IWADC-2003-29.pdf
- DOI:
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