LFSR-Based Performance Characterization of Nonlinear Analog and Mixed-Signal Circuits

Abstract

This paper presents an efficient pseudorandom (PR) test method to characterize the performance of nonlinear analog and mixed-signal (AMS) circuits including those embedded in SoC devices. Previous applications of the PR test method to BIST have been limited to digital and linear analog circuits. In this paper, we extend the application of PR test to nonlinear AMS circuits. In doing so, we reduce the cost of testing nonlinear circuits, and increase the test coverage of embedded AMS circuits without incurring a large area overhead to accommodate a test stimulus generator. Our method maintains good test accuracy by using a Volterra series model to describe the behavior of the device under test (DUT). A PR sequence generated from a simple LFSR is used to excite the DUTs over a wide range of frequencies and estimate the parameters of the Volterra series, which are then used to predict the performance of DUTs. We present a method to reduce the test time by using a compressed cross-correlation method which reduces the complexity of the presented algorithm. The mathematical background and hardware measurement results are presented to validate our method.