A new technique for generating approximate symbolic expressions for network functions in linear(ized) analog circuits is presented. It is based on the compact determinant decision diagram (DDD) representation of the circuit. An implementation of a term generation algorithm is given and its performance is compared to a matroidbased algorithm. Experimental results indicate that our approach is the fastest reported algorithm so far for this application.

This paper presents a novel method to automatically generate symbolic expressions for both linear and nonlinear circuit characteristics using a template-based fitting of numerical, simulated data. The aim of the method is to generate convex, interpretable expressions. The posynomiality of the generated expressions enables the use of efficient geometric programming techniques when using these expressions for circuit sizing and optimization. Attention is paid to estimating the relative `goodness-of-fit' of the generated expressions. Experimental results illustrate the capabilities of the approach.