Accurate and efficient predictions of statistical circuit performance spreads

The requirements for ever-decreasing design times and processing costs associated with, for example, ASIC design have meant that ensuring circuit manufacturability must now be considered to be an integral step in the IC design framework. An efficient and accurate methodology for the prediction of essentially unavoidable statistical circuit performance variations, which is suitable for implementation into a circuit simulator, is presented. Most reported statistical design techniques are aimed at digital design applications, so emphasis has been given in this work to predicting the behaviour of analog circuitry which may be critical in some mixedsignal ASIC applications. The statistical design technique implemented employs measured model parameter data on which a principal component analysis is performed. Circuit sensitivity information also contributes to the efficiency of this methodology.