| 摘要 |
PURPOSE:To facilitate and shorten the process and time of diagnostic design by classifying troubles of the scanning circuit by operation sequences for detecting the trouble in advance and storing scanning operation sequences for detecting the trouble of each classified trouble group. CONSTITUTION:Assuming such a single degenerative trouble model that there is one trouble wherein the value of the input and output signal lines of a logic element in the circuit is fixed at 0 and 1, only one trouble is assumed in the scanning circuit. Therefore, when specific trouble is assumed, a scanning operation sequence for detecting the trouble can be determined. In other words, when the scanning operation sequence is determined, the trouble detected by it is determined. Namely, troubles detected by a certain scanning operation sequence are gathered and then grouped. Then a scanning operation sequence is selected properly according to a table to determine a set of scanning operation sequences for a test which detect all troubles. Test patterns are generated for all sets and the trouble detection rate is increased up to 100%. |
