Stability Analysis of Active Impedance Inverter based on Loss-compensated Passive Structure

An active impedance inverter, comprising negative (non-Foster) capacitors have been used recently in tunable bandpass filter designs. Those filters used a negative capacitor based on the well-known Linvill’s topology, while the design based on a loss-compensated passive structure has been proposed very recently. Here, we compare the stability properties of active impedance inverters based on both kinds of negative capacitor, loaded with commonly used complex loads.