Simulation-based generation of posynomial performance models for the sizing of analog integrated circuits

This paper presents an overview of methods to automatically generate posynomial response surface models for the performance characteristics of analog integrated circuits based on numerical simulation data. The methods are capable of generating posynomial performance expressions for both linear and nonlinear circuits and circuit characteristics, at SPICE-level accuracy. This approach allows for automatic generation of an accurate sizing model for a circuit that composes a geometric program that fully describes the analog circuit sizing problem. The automatic generation avoids the time-consuming and approximate nature of handcrafted analytic model generation. The methods are based on techniques from design of experiments and response surface modeling. Attention is paid to estimating the relative "goodness-of-fit" of the generated models. Experimental results illustrate the capabilities and effectiveness of the presented methods.