Generalized Analysis of High-Order Switch-RC$N$-Path Mixers/Filters Using the Adjoint Network

摘要

This paper presents a systematic method to analyzen$N$n-path mixers and filters consisting of periodically switchedn$RC$n-networks of arbitrary order. It is assumed that each capacitor periodically exchanges charge with the rest of the network during the on-phase of the switching clock, then samples its charge, and holds it perfectly until the next on-phase. This assumption allows for using the adjoint network for simplified analysis of the harmonic transfer functions that describe the signal transfer and folding. Moreover, harmonic transfer cancellations due to then$N$n-path implementation withn$N$nequal capacitors switched byn$N$nnon-overlapping clocks are systematically analyzed. The method is applied to a recently publishedn$N$n-path filter-mixer combination and verified by simulations.