A Multi-polynomial LFSR Based BIST Pattern Generator for Pseudorandom Testing

In this paper, a new linear feedback shift register (LFSR) structure for scan-based built-in self-test (BIST), which has at least two characteristic polynomials, is proposed. Multiple polynomials are utilized to generate the pattern sequences for feeding the scan chain of the circuit under test in pseudorandom testing phase. Using the proposed LFSR, same or even better fault coverage can be achieved in pseudorandom testing phase with less hardware cost, hence can also reduce the test application time in deterministic testing phase. Experimental results demonstrate the advantages of the proposed LFSR over the conventional ones.