A 14-bit extended-range incremental ΣΔ ADC matlab-model based on 90nm CMOS-technology

In this paper a complete Matlab-Based-Model of a high resolution second-order multi- channel incremental A-to-D-Converter is presented. The A-to-D-Converter model includes the most relevant non-idealities for future transistor- level implementation. The reference technology used for the model is the 90nm CMOS node. The analog part of the A-to-D-Converter will be implemented by switched-capacitors integrators, so that the passive components and MOS transistor matching parameters are included in the Model. CMOS Process deviation is also taken into account, since the Matlab-Based model has the feature to set the Opamp finite dc-gain and bandwidth. External slew-rate limitation is also modeled in the Opamp. The system complies with the overall specifications of the biomedical systems and combines the advantages of oversampling with resolution improvement thanks to an extended-counting-based technique. The final simulations results validate the model, with a signal-to-noise-distortion ratio of 92.1 dB within a 500 kHz bandwidth at a 16 MHz sample frequency.