ANSYS, Inc.
Low-dropout regulator and charge pump modeling using frequency-domain fitting methods

Abstract:

Computer-implemented systems and methods are provided for modeling a charge pump. A relationship between an output voltage of the charge pump and a loading condition is determined. A frequency-domain analysis is performed at multiple frequencies to determine an impedance function representative of the charge pump's impedance at each of the multiple frequencies. A vector-fitting algorithm is applied to approximate the impedance function using a plurality of poles and residues. A circuit is synthesized based on the plurality of poles and residues. A model for the charge pump is generated, where the model includes the synthesized circuit and components that model the relationship between the output voltage and the loading condition.