This paper investigates the use of multiple-polynomial linear feedback shift registers (MP-LFSRs) for dynamic reseeding in a continuous flow test compression environment to allow a more aggressive expansion of tester channels to scan chains and thereby increase the amount of test compression achieved. A scheme is proposed that does not need any control data to be used to select the polynomial that decompresses each test cube. This problem is formulated as a bipartite matching problem. The amount of hardware used to implement the MP-LFSR is reduced by exploiting the property that the reciprocal of a primitive polynomial is also primitive. Also, a procedure for optimally using an MP-LFSR with retained free-variables [Muthyala 12] is described. Experimental results are presented showing the improvements in test compression that can be obtained with MP-LFSRs.
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