SYSTEM AND METHOD FOR BIT-WISE SELECTIVE MASKING OF SCAN VECTORS FOR X-VALUE TOLERANT BUILT-IN SELF TEST

A system and method are provided for selective bit-wise masking of X-values in scan channels in an integrated circuit (IC) during a built-in self test (BIST). The composite mask pattern is selectively generated according to locations of X-values identified in a simulation of the IC. The composite mask pattern is stored on the IC and cyclically maintained while being applied to the operational scan results of the IC. The composite mask pattern is recycled over a plurality of scan iterations to effectively prevent the X-values from influencing the resulting signature of the BIST that represents a functional fingerprint of the IC and minimize storage requirements for the composite mask pattern.