Multi‐cycle broadside tests with runs of constant primary input vectors
Irith Pomeranz · IET Computers & Digital Techniques · 2013
Multi‐cycle tests, with two or more functional clock cycles between scan operations, can be used for test compaction. When tester limitations prevent primary input vectors from being changed at‐speed, one of the possible solutions is to hold the primary input vector constant during the functional clock cycles of a multi‐cycle test. However, this limits the level of test compaction that can be achieved. To provide an alternative to this solution, a new type of multi‐cycle tests has been defined, where the primary input vector is changed during a clock cycle that is applied under a slow clock. This is followed by a run of the same vector applied under a fast clock. Transition faults are activated during the clock cycles that are applied under a fast clock. A test generation procedure that produces such test sets for transition faults has also been described. Experimental results demonstrate that the new type of tests can improve the ability to produce a compact test set for certain benchmark circuits.