PIDISC: pattern independent design independent seed compression technique

A novel scheme for compressing the seeds of a linear feedback shifter register (LFSR) is presented. Instead of storing the seeds of the LFSR in the tester, the scheme compresses the seeds and stores them in the tester. The compression scheme can be used with any variation of static LFSR reseeding. An important feature of the proposed scheme is that the decompressor is test pattern and design independent and can be implemented with very little area overhead. Experimental results show that seed compression can improve overall compression by a factor of 7× for large industrial circuits.