Jg. Mueller et al., A MULTIFREQUENCY TECHNIQUE FOR FREQUENCY-RESPONSE COMPUTATION WITH APPLICATION TO SWITCHED-CAPACITOR CIRCUITS WITH NONLINEARITIES, IEEE transactions on computer-aided design of integrated circuits and systems, 15(7), 1996, pp. 775-790
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.