An Approach to Locate Parametric Faults in Nonlinear Analog Circuits

Aiming at the problem to locate parametric faults in nonlinear analog circuits, a new approach based on the subband decomposition combined with coherence functions is proposed. First, the Volterra series of the circuit under test decomposed by wavelet packets are used to detect the parametric faults. Then, the Volterra series in subbands are used to calculate the coherence functions. By comparison with the fault signatures, different states of the parametric faulty circuits are identified, and the faults are located. Simulations show the effectiveness of the method of the fault diagnosis in nonlinear circuits.