Bit-swapping LFSR for low-power BIST

A modified linear feedback shift register (LFSR) is presented that reduces the number of transitions at the inputs of the circuit-under-test by 25% using a bit-swapping technique. Experimental results on ISCAS´85 and 89 benchmark circuits show up to 45% power reduction during test. They also show that the proposed design can be combined with other techniques to achieve a very substantial power reduction of up to 63%.