Test Length for Pseudorandom Testing

The process of determining the required test length for a desired level of confidence for pseudorandom testing using a random sampling without replacement model is examined. The differences between random and pseudorandom testing are discussed and developed. The strictly random testing model is shown to be inaccurate for high confidence testing of combinational circuits. A method of calculating the required test length for pseudorandom testing based upon fault detectabilities is described. The result provides a very accurate prediction of required test length applicable to self-test using pseudorandom inputs.