Fault Detection and Location Using IDD Waveform Analysis

| This paper investigates online testing for fault localization in CMOS circuits using IDD waveform analysis. The methods investigated in this paper are applicable both to static as well as dynamic CMOS circuits. We show that not only can IDD waveform analysis detect a number of defects that are otherwise undetectable by IDDQ testing, it can also be applied to online testing and diagnosis of CMOS circuits. In particular, we compare two IDD based analysis techniques; An integrator based analysis; and, a fast Fourier transform (FFT) based analysis. The approach used for locating faults is based on the measurement of the delay after which the faulty circuit response diiers from the fault-free circuit response in a levelized circuit under test (CUT). We consider highly regular structures as well as random logic to demonstrate that fault localization using this approach is possible in a variety of circuits.