Nonideal performance of single amplifier simulated frequency dependent negative resistances

The effect of the nonideal characteristics of operational amplifiers such as finite frequency dependent gain and output impedance on the performance of some single amplifier simulated frequency dependent negative resistances (FDNR´s) is analyzed. Equivalent circuits showing the parasitic elements due to nonideal characteristics of amplifier are given. In two configurations the FDNR is shown to have resistive and inductive parasitic elements in addition to series and shunt capacitances. The experimental results confirm the validity of the equivalent circuits. The effect of the slew rate of the operational amplifier on the maximum signal-handling capability is studied. The analysis and equivalent circuits give a clear physical concept of the effect of the nonideal amplifier characteristics on the simulated FDNR´s and can be used for´predistorted design of filters with practical FDNR´s.