Synthesis of a leapfrog configuration equivalent to an LC-ladder filter between generalized terminations

Leapfrog RC active filters are known to be insensitive to the value of the elements thanks to their analogy to LC filters. It is shown that the class of LF filters amenable to such an analogy can be enlarged by considering nondissipative 2-ports between generalized dissipative terminations. There is no necessity for transmission zeroes at the origin or at infinity, which was the case in the previous approaches. The formulas linking the given transmittance to the LC 2-port description are derived and the optimal choice of the remaining degrees of freedom are discussed. The method presented here preserves the analogy between the LF design and its LC equivalent since this analogy guarantees the low sensitivity; yet it is totally free from all constraints originating from the LC implementation and irrelevant for the LF design.