METHOD FOR DISCRIMINATING BETWEEN UNTESTABLE FAILURE AND REDUNDANT FAILURE IN SEQUENTIAL LOGIC CIRCUIT

摘要

PROBLEM TO BE SOLVED: To discriminate between redundant failure and untestable failure by selecting one lead in a sequential circuit and performing analysis while assuming that the sequential circuit can not take first or second value during a given frame of starting time. ;SOLUTION: When a fabricated circuit 12 is tested, an input stimulus is generated from a test generator 11 and applied to the primary input 14 of the circuit 12 and then an output response is measured on the primary output 15. A comparator circuit 16 compares the output response with an expected output response and identifies the failure in the circuit. The test process is normally carried out under control of a computer in an automatic test equipment(ATE). Each circuit to be tested is normally plugged in the ATE system through a standardized interface.;COPYRIGHT: (C)1996,JPO