NODAL ANALYSIS OF SWITCHED-CURRENT FILTERS

This paper describes an efficient and relatively simple approach to th e systematic analysis of ideal, or near ideal, switched-current filter s [1]-[5]. The proposed technique is based on the nodal analysis of a linear resistive network that models the behavior of the filter for sm all signals, allowing the use of any practical topology and the inclus ion of important imperfections, as output resistances of MOS transisto rs, series resistances of current-conducting switches, and parasitic c apacitances. Techniques for frequency-domain analysis, z-transforms ca lculations, time-domain analysis, and frequency-domain sensitivity ana lysis are discussed. The method is not restricted to the analysis of t he particular structures of switched-current filters. It can be easily generalized for the analysis of a wide class of periodically switched RC-active circuits, where it is assumed that the circuits stabilize b etween the switching instants.