Testability enhancement for control-flow intensive behaviors

A BIST-based test synthesis methodology for control-flow intensive behavior s is proposed. This methodology targets the control statements in a behavio ral description, such as if-then-else and loop statements, because such sta tements can introduce testability problems in the resulting circuit. How we ll the operations in each branch of a control statement can be tested depen ds on the probability of taking each branch and the quality of the test pat terns used in each branch. Behavioral modifications are presented that can resolve these testability issues. The proposed methodology systematically i dentifies poor testability areas within a behavior and applies the behavior al modifications to improve the testability. Experimental results from six practical examples show that this technique is effective.