Modeling ceramic and tantalum capacitors by automatic SPICE parameter extractions

SPICE models are proposed to represent the complex frequency-dependent behaviors of impedance and equivalent series resistance (ESR) for both ceramic and tantalum capacitors. Due to the highly non-linear structures of the models to fit the complex frequency-dependent characteristics of real world capacitors, efficient and robust optimization methods which yield good accuracy are developed to overcome the difficulty of extracting model parameters by analytical optimization approaches. These capacitor models are able to accurately match the measured data over a wide frequency range and are useful for optimizing the performances of power conversion circuits with the aid of computer simulations.