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.