Transformation of LC-filters to active RC-circuits via the two-graph method

This paper proposes a novel method of synthesis of active RC-filters. The process is based on the use of the classical LC-network. The constructed equivalent active circuit uses a kind of active switches, i.e. nullators and norators that ensure ‘switching’ between voltage graphs and current graphs. Accordingly, parameters of the constructed circuit depend only on the values of resistors and capacitors and not on the parameters of the active elements. The proposed approach is illustrated through two examples. SPICE simulation results are given to show viability of the proposed method.