A Rare Event Based Yield Estimation Methodology for Analog Circuits

Abstract

With the growing use of analog circuits in sensor systems for internet of things applications, estimation of their yield has become critical in order to increase the efficiency of large volume manufacturing. In this paper, a methodology to estimate the yield of analog circuits beyond 95% is proposed. The methodology is based on an algorithm that uses adaptive sampling to approach the “tail” region of the initial distribution which contains the dysfunctional units. These units do not satisfy the initial design targets thereby lowering the yield. An inverter and a two-stage operational amplifier have been used to verify the methodology where the reference distribution is based on 10^6 samples for both circuits. Simulation results reveal that the accuracy for 95%, 98%, and 99% yield has been compromised by less than 2.1%, 5.7%, and 7.4%, respectively, whereas the computation cost is reduced by 20x.