Active RC Synthesis for Significant Reduction in Magnitudes of Reactive Elements

Active elements may be used to significantly reduce the total reactance required in a network. This paper presents two active RC synthesis techniques for this purpose. One method employs a negative-impedance-converter to realize any number of system poles and reduces the total required capacitance to any desired extent. The resulting design is, however, very sensitive to active and passive parameter values. The second method also permits any prescribed total capacitance but employs a cascade of isolated second-degree sections. Two such sections are presented and optimized with respect to a figure of merit
C_{t}AS_{A}
, being the product of total capacitance, required active element gain and system sensitivity to the latter. System transmission zeros may be accommodated to a certain extent.