Variability-aware reliability simulation of mixed-signal ICs with quasi-linear complexity

Abstract

This paper demonstrates a deterministic, variability-aware reliability modeling and simulation method. The purpose of the method is to efficiently simulate failure-time dispersion in circuits subjected to die-level stress effects. A Design of Experiments (DoE) with a quasi-linear complexity is used to build a Response Surface Model (RSM) of the time-dependent circuit behavior. This reduces simulation time, when compared to random-sampling techniques, and guarantees good coverage of the circuit factor space. The DoE consists of a linear screening design, to filter out important circuit factors, followed by a resolution 5 fractional factorial regression design to model the circuit behavior. The method is validated over a broad range of both analog and digital circuits and compared to traditional random-sampling reliability simulation techniques. It is shown to outperform existing simulators with a simulation speed improvement of up to several orders of magnitude. Also, it is proven to have a good simulation accuracy, with an average model error varying from 1.5 to 5 % over all test circuits.