A CLASS OF 2-DIMENSIONAL CELLULAR-AUTOMATA AND THEIR APPLICATIONS IN RANDOM PATTERN TESTING

A basic framework to characterize the behavior of two-dimensional (2-D) cellular automata (CA) has been proposed. The performance of the regular structure of the 2-D CA has been evaluated for pseudo-random pattern generation. The potential increase in the local neighborhood structure for 2-D CA has led to better randomness of the generated patterns as compared to LFSR and 1-D CA. The quality of the random patterns generated with 2-D CA based built-in-self-test (BIST) structure has been evaluated by comparing the fault coverage on several benchmark circuits. Also a method of synthesizing 2-D CAs to generate patterns of specified length has been reported. The patterns generated can serve as a very good source of random two-dimensional sequences and also variable length parallel pattern generation having virtually nil correlation among the bit patterns.