An immunity modeling technique to predict the influence of continuous wave and amplitude modulated noise on nonlinear analog circuits

An innovative method to model, in the early design stage, the behavior of nonlinear analog circuits in the presence of noise is presented. The technique relies on Harmonic Balance analysis and the obtained model does not only efficiently predict the influence of a continuous wave disturbance, it may also be used to quickly estimate the device´s behavior while being subjected to amplitude modulated noise. The method leverages surrogate models, as such reducing the simulation time and concealing the intellectual property of the circuit manufacturer. Moreover, the model can be easily integrated into a circuit simulator. An industrial case study of a voltage regulator for automotive applications is described in this contribution and it clearly confirms the capabilities of the method.