Fault detection and diagnosis of k-UCP circuits under totally observable condition

A method is presented for detecting stuck-open faults, as well as stuck-at faults, in CMOS combinational circuits by short test sequences of fixed length. The discussion is based on the assumption that outputs of all the gates in a circuit are observable. This assumption will become reasonable when a new testability solution called CrossCheck, or a new test equipment, called on electron-beam tester, is used. The concept of k-UCP (uniform, having a (k+1)-Color solution and compatible polarity) circuits is introduced, and it is shown that 2(k+1) kinds of test sequences of length k(k+1)+1 are sufficient to detect stuck-open faults, as well as stuck-at faults in a k-UCP circuit. Furthermore, it is shown that single stuck-open faults can be located by using a fault diagnosis table. A method which can speed up the generation of a fault diagnosis table is also proposed.<>