Analysis of the Influence of Component Mismatch on Integrated Passive Polyphase Filters

Passive Polyphase Filters (PPF) are extensively used in analog signal processing system which work with quadrature signals, either filtering or generating it. However, the quality of PPF performance in these kinds of operation rely on a perfect matching in components and a symmetrical topology. Thus, mismatch effects could produce notable degradation in PPF response. Despite this, mismatch impact in PPF has not been thoroughly analyzed previously in literature to the best of authors knowledge. In this work, a systematic method is proposed to search the worst possible mismatch in a PPF with any number of stages for a certain tolerance. Then, for the 1-stage case, both PPF types (I and II) are analyzed to evaluate how this non-ideality alters the response of this kind of filters.