A MULTIFREQUENCY TECHNIQUE FOR FREQUENCY-RESPONSE COMPUTATION WITH APPLICATION TO SWITCHED-CAPACITOR CIRCUITS WITH NONLINEARITIES

Frequency domain analysis of switched-capacitor and other clocked circ uits including nonlinearities is a difficult problem requiring special attention, Conventional nonlinear frequency response methods are comp utationally intensive and time consuming for circuits with large trans ient components, In this paper, we present a novel technique for the r apid estimation of the nonlinear frequency response of switched-capaci tor circuits, The analysis technique is formulated using a multifreque ncy sinusoidal excitation to drive the circuit into its steady-state c ondition, Then, the fundamental components are extracted using a frequ ency-directed Discrete Fourier Transform (DFT) in order to construct t he frequency response, The key steps of this approach include the sele ction of noninterfering input frequencies and the determination of pro perly scaled input amplitudes, In addition, a method is proposed to re ach steady-state quickly and to detect the steady-state condition for use in conjunction with the multifrequency approach described here.