GLFSR-a new test pattern generator for built-in-self-test

A new and effective pseudo-random test pattern generator, termed GLFSR, is introduced. These are linear feedback shift registers over a Galois field GF(2^δ), (δ>1). Unlike conventional LFSRs, which are over GF(2), these generators are not equivalent to cellular arrays, and are shown do achieve significantly higher fault coverage. Experimental results are presented in this paper depicting that the proposed GLFSR can attain fault coverage equivalent to the LFSR, but with significantly fewer patterns. Specifically, results obtained demonstrate that in combinational circuits, for both stuck-at as well as transition faults, the proposed GLFSR outperforms all conventional pattern generators. Moreover, these experimental results are validated by certain randomness tests which demonstrate that the patterns generated by GLFSR achieve a higher degree of randomness