Accurate Performance Estimation using Circuit Matrix Models in Analog Circuit Synthesis

Optimization based sizing methods allow automating the synthesis of analog circuits. Automated analog circuit synthesis techniques depend on fast and reliable estimation of circuit performance. This paper presents a highly accurate method of estimating performances by constructing models of the circuit matrix instead of the traditionally used performance models. Device matching in analog circuits is utilized to identify identical elements in the circuit matrix and reduce the number of elements to be modeled. Experiments conducted on benchmark circuits demonstrate the effectiveness of the method in achieving correct performance prediction. Results show that the performances can be predicted within a mean error of 0.1% compared to a SPICE simulation. Techniques such as hashing and near neighbor searches are proposed to expedite the matrix model evaluation procedure. These techniques avoid recomputations by saving previously visited solutions. The procedure is used for synthesizing analog circuits from various specifications such as performance parameters, frequency response. The proposed method gives accurate results for synthesis for various types of circuit specifications.