Symbolic Techniques for Evaluating Complex Custom Circuits

Brown University, Providence RI

Investigators

Abstract

This research focuses on the development of symbolic formulations for timing and reliability analysis that can handle a wide range of custom-designed, complex circuits in an efficient, cost-effective manner. This symbolic approach enables handling of any arbitrary circuit structure and allows for an efficient means of incorporating information on the functional operation of the circuit into the analysis. Two areas are being explored: (1) Symbolic algorithms are being developed to analyze electrical noise problems due to such things as leakage currents and charge sharing. To improve accuracy, the analysis is constrained by timing and input conditions. Based on the results of this analysis, circuits may be flagged for design violations or automatically re-designed to improve electrical reliability. (2) Symbolic formulations to calculate the delay through a channel-connected region (CCR) of CMOS devices are be developed. These formulations will handle nearly all commonly-used digital circuit families, as well as handle multiple inputs transitioning and accept arbitrary input-exclusivity constraints. The goal of this work is to develop an efficient means to identify problem circuits for further analysis while avoiding the need to verify many non-realizable worst-case conditions with other more costly simulation techniques.