A high-level modeling framework for the design and optimization of complex CT functions

Novel CMOS technologies are rapidly migrating towards the nanometer world. The design and optimization of complex analog circuits employing these processes is impracticable when using only transistor-level electronic design automation (EDA) tools. Efficient design methodologies including behavioral modeling are inevitable, but the high-level models should incorporate accurate circuit characteristics and technological limitations. One solution consists in using a refined top-down design process where the macro-models are extracted from the analog block elements (e.g. amplifiers, filters) implemented on specific technologies. These fast-simulating models can be used for the high-level simulation and optimization of the entire system. We propose in this paper a complete design methodology employing the above elements and the corresponding application framework based on the interface between MATLAB and CADENCE software tools. SIMULINK and VHDL-AMS are used for the high-level system modeling. A continuous-time (CT) Sigma-Delta modulator application is presented.