In this paper we present a method for
stability analysis of high order Sigma-Delta modulators.
The method is based on a parallel decomposition of the
modulator. Using this presentation the general N-th
order modulator could be considered as made up of N
first order modulators, which interact only through the
quantizer function. The decomposition helps us to
extract the stability conditions of the N-th order
modulator. They are determined by the stability
conditions of each of the first order modulators but
shifted with respect to the origin of the quantizer
function, because of the influence of all other first order
modulators.