Parametric Fault Diagnosis of Nonlinear Analog Circuits Using Polynomial Coefficients

We propose a method for diagnosis of parametric faults in analog circuits using polynomial coefficients of the circuit model. As a sequel to our recent work, where circuit response is modeled as polynomial for uncovering parametric faults in nonlinear circuits, we propose diagnosis of such faults using sensitivity of coefficients of the estimated polynomial to circuit parameters. The proposed method requires no design for test hardware as might be added to the circuit by some other methods. The proposed method is illustrated for a benchmark elliptic filter. It is shown to uncover several parametric faults causing deviations as small as 5% from the nominal values.