Modern approaches to design of multi-channel delta-sigma ADCs

Incremental delta-sigma ADC (IADC) and memoryless delta-sigma ADC are described. These two approaches allow to utilize a delta-sigma ADC, known for its increased resolution, in multi-channel systems due to the inter-sample interference suppression that two mentioned structures provide. In this paper, MATLAB/Simulink models of the mentioned structures are presented. In particular, limiting blocks are added to take into account nonlinearities due to finite power supply of integrators; coefficients of delta-sigma modulators were selected so as to maximize their signal-to-noise ratio; parameters of the raised cosine filter were selected to minimize crosstalk between channels. Results of simulations, namely power spectral density of the output signals and signal-to-noise ratio of the output signals, confirm operability of the described structures.