System and Method for Adaptive Nonlinear Test Vector Compression

摘要

A system comprises a decompressor configured to receive an input test vector and to generate an output vector in response to the input test vector. A decoder couples to the decompressor and comprises a reset pattern detector, a lookup table, and control logic. The reset pattern detector (RPD) is configured to scan the output vector to identify a predetermined reset pattern. The control logic couples to the RPD and the lookup table and is configured to direct operation of the lookup table in a first mode or a second mode based on whether the output vector comprises the predetermined reset pattern, as identified by the RPD. The lookup table is configured to receive the output vector, to operate in the first mode, comprising storing one of a plurality of codeword sets, each codeword set comprising a plurality of pairs of codewords and associated data; and to operate in the second mode, comprising generating test data blocks in response to identified codewords in the output vector.;A method for adaptive test data compression includes receiving an input vector. The input vector is decompressed to generate an output vector. A determination is made whether the output vector comprises a reset pattern. In the event the output vector comprises a reset pattern, one of a plurality of codeword sets is loaded into a lookup table; each codeword set comprising a plurality of pairs of codewords and associated data. In the event the output vector does not comprise a reset pattern, codewords in the output vector are identified and test data blocks are generated in response to identified codewords.