Multifrequency analysis of faults in analog circuits

Analog Circuit Specification Testing by Means of Walsh–Hadamard Transform and Multiple Regression Supported by Evolutionary Computations

“…The 100 patterns for the CUT discrete elements parameters dispersed randomly in their tolerance regions δ DEV = ± 5% (set I) and for eight Table 4 CUT performance parameters estimation errors and their standard deviations assumed special cases with the one selected element value shifted from the nominal point and randomly determined other ones (set II) were tested during this experiment. The filter circuit performance parameters were calculated basing on the regression models found evolutionarily (22)(23)(24)(25)(26)(27)(28)(29)(30)(31). Finally, identically as in [31], the CUT pattern is classified into the good ones if all the tested performance parameters do not exceed the allowed tolerance absolute deviation ± | p i | from the nominal level specified and to the faulty ones otherwise ( Table 5).…”

“…Catastrophic fault detection method dedicated to nonlinear circuits was described in [29]; however, work [30] presents the technique dedicated to the diagnosis of spot defects. In works [24,26,27], the approaches based on sensitivity analysis for faulty element identification, test measurements ambiguity sets determination and optimal frequency of testing signal selection, respectively, may be found. The example solution for CUT functional correctness verifying by investigating voltage levels at specific time points of response of CUT excited by a specialized PWL testing stimulus was presented in [31].…”

Visualization of Circuit Card EM Fields.

“…For understanding the program, the important commands are: For testing purposes, Aztec generated circuits for testing with the following 2-input logical devices: AND gates, NAND gates, OR gates, NOR gates, and JK flip-flops. 36 For ease in constructing our test circuits, we have restricted ourselves to circuits that have the appearance of figure 66. This circuit has n inputs, shown on the left.…”

“…To analyze their data and identify faults on circuit cards, they used artificial neural networks, edge finding, FFTs, and image processing. They did not collect data at multiple frequencies, as we did (although their final report recommended the use of data gathering at multiple frequencies-see also [36]). Figure 1 (from [38]) represents the magnetic field above two circuit boards (their magnetometer had a physical diameter of 0.1 inch), one of the two circuit boards had faults.…”

Robust optimization based backtrace method for analog circuits

“…The DC tests [3,4] are simple develop and apply, and are mainly used as screening tests to reject obviously defective circuits. AC tests [8,9] are based on multi-tone periodic stimuli, and are typically used to test a class of circuits whose specifications are strongly related to frequency domain behavior of the circuit. Transient tests [10,5,11,12] are superset of AC and DC tests, hence offering higher fault and yield coverage(see [13] for defns) and greater flexibility in applying complex test sequences.…”