Low-output-impedance electronically adjustable universal filter using voltage differencing buffered amplifiers

In this study, a voltage-mode universal filter with three inputs and single output is presented. The circuit is resistor-less, and consists of only two VDBAs and two capacitors. The proposed TISO filter realizes all the five standard biquadratic filter functions at the low-impedance-output terminal without any component matching criterion. The effect of the VDBA non-idealities on the presented filter performance is also discussed in detail. To prove the theoretical finding, simulation results are provided using PSPICE software.