Synthesizing switched-current filters by transposing the SFG of switched-capacitor filter circuits

摘要

A general synthesis method for switched-current (SI) filter circuits is presented. The SI filter circuit is obtained from the transpose of the signal-flow-graph (SFG) representation of a switched-capacitor (SC) filter realization. The resulting SI circuits realized the same transfer function as the SC filter circuit and, in addition, possess identical component sensitivities. Since the operation of SFG transposition is sensitivity preserving, application of the proposed method to low-sensitivity SC filter circuits will produce low-sensitivity SI filter circuits.