Affiliation:
1. Electronics and Electrical Communications Engineering Department, Ain Shams University, Cairo 11517, Egypt
Abstract
The sigma-delta modulator (SDM) is one of the well-established data converter architectures. It is well-known for achieving a high signal-to-noise ratio (SNR). In the SDM, the integrators in the loop filter could suffer from overloading if the signal swing exceeds its maximum level, which leads to performance and SNR degradation. Thus, scaling the system coefficients is needed, such that there is no overloading for the integrators. In this work, we present a systematic general method that could be used for scaling the signal swings in the continuous-time low-pass sigma-delta modulator (SDM). The proposed method can be applied to any continuous-time low-pass SDM architecture, and it includes the scaling of all the possible combinations of the system coefficients. Moreover, an open-source Simulink-based toolbox that includes the systematic method is presented. This toolbox could help the designer to execute the scaling process and the simulations in an efficient way. In addition to that, a design example is discussed to illustrate the proposed method, wherein the presented toolbox is used for simulations, and the simulation results are shown.
Subject
General Earth and Planetary Sciences
Reference31 articles.
1. Analysis and design of a high speed continuous-time ΔΣ modulator using the assisted OPAMP technique;Jain;IEEE J. Solid-State Circuits,2012
2. Caldwell, T., Alldred, D., Schreier, R., Shibata, H., and Dong, Y. (2014, January 15–17). Advances in high-speed continuous-time Delta-sigma modulators. Proceedings of the IEEE 2014 Custom Integrated Circuits Conference, San Jose, CA, USA.
3. de La, R.J.M. (2019). Sigma-Delta Converters Practical Design Guide, Wiley-IEEE Press. [2nd ed.]. Chapter 2.
4. Pavan, S., Schreier, R., and Temes, G.C. (2017). Understanding Delta-Sigma Data Converters, Wiley. [2nd ed.]. Chapter 8.
5. Beilleau, N., Aboushady, H., and Louerat, M.M. (2003, January 27–30). Systematic approach for scaling coefficients of discrete-time and continuous-time sigma-delta modulators. Proceedings of the 46th Midwest Symposium on Circuits and Systems 2003, Cairo, Egypt.