3-Weight Pseudo-Random Test Generation Based on a Deterministic Test Set
Irith Pomeranz, Sudhakar M. Reddy · 2005
A method for weighted pseudo-random test generation based on a deterministic test set is described. The main advantages of the method over existing methods are: (1) only three easily generated weights, {0,0.5,1), are used, (2) minimal length LFSR is used, thus leading to minimal hardware for built-in-test applications, and (3) the weights are selected to allow the same coverage of target faults, attained by the deterministic test set, to be attained by weighted random patterns. The weights are computed by walking through the range of test generation approaches from pure random at one extreme to deterministic at the other extreme, dynamically selecting the weight assignments to correspond to the remaining faults at every stage. Hardware for the generation of random patterns under the proposed method is described. Experimental results are provided for ISCAS-85 benchmarks.