Reconfigurable broadcast scan compression using relaxation-based test vector decomposition

An effective reconfigurable broadcast scan compression scheme that employs partitioning of test sets and relaxation-based decomposition of test vectors is proposed. Given a constraint on the number of tester channels, the technique classifies test sets into acceptable and bottleneck vectors. The bottleneck vectors are then decomposed into a set of vectors that meets the given constraint. The acceptable and decomposed test vectors are partitioned into the smallest number of partitions while satisfying the tester channels constraint to reduce the decompressor area. Thus, the technique by construction satisfies a given tester channel constraint at the expense of an increased test vector count and number of partitions, offering a tradeoff between test compression, the test application time and the area of test decompression circuitry. Experimental results demonstrate that the proposed technique achieves better compression ratios compared with other techniques of test compression.