Title :
Empirical bounds on fault coverage loss due to LFSR aliasing
Author :
Debany, Warren H. ; Gorniak, Mark J. ; Daskiewich, Daniel E. ; Macera, Anthony R. ; Kwiat, Kevin A. ; Dussault, Heather B.
Author_Institution :
Rome Lab., RL/ERDA, Griffiss AFB, NY, USA
Abstract :
Linear-feedback shift registers (LFSRs) are often used to compact test responses. Prior analyses, based on statistically-independent error models, have predicted that aliasing probability ´converges´ to 2/sup -k/ for LFSR polynomials of degree k, and that primitive polynomials perform better than nonprimitive polynomials. This paper presents the first statistical results based on full fault simulation that confirm these predictions. However, the average aliasing probability is not by itself a useful measure of the loss of fault detection information; the authors introduce an upper confidence limit (UCL) for the loss of fault coverage. The ´ideal´ UCL is shown to match closely the empirically-derived UCL.<>
Keywords :
built-in self test; fault location; logic testing; polynomials; sequential circuits; shift registers; LFSR aliasing; aliasing probability; fault coverage loss; nonprimitive polynomials; primitive polynomials; test responses; upper confidence limit; Circuit faults; Circuit testing; Electrical fault detection; Fault detection; Laboratories; Logic circuits; Phase frequency detector; Polynomials; Probability; Shift registers;
Conference_Titel :
VLSI Test Symposium, 1992. '10th Anniversary. Design, Test and Application: ASICs and Systems-on-a-Chip', Digest of Papers., 1992 IEEE
Conference_Location :
Atlantic City, NJ, USA
Print_ISBN :
0-7803-0623-6
DOI :
10.1109/VTEST.1992.232739