Testability enhancement for behavioral descriptions containing conditional statements

A high-level test synthesis methodology based on BIST is proposed. This methodology targets the conditional if-then-else statements in a behavioral description because such statements can introduce testability problems in the resulting circuit. How well the operations in each branch of a conditional statement can be tested depends on the probability of taking each branch and the quality of the test patterns used in each branch. Behavioral modifications are presented that can resolve these testability issues. Experimental results from three practical examples show that this technique is effective.