Electronically tunable versatile voltage-mode MIMO OTA-C universal filter

This paper presents a new versatile high input impedance voltage-mode universal filter with multiple-input multiple-output (MIMO) based on single-ended operational transconductance amplifiers (OTAs) and grounded capacitors. The proposed circuit can work as a two-input four-output filter and a three-input single-output filter without changing the circuit topology. The natural frequency (ω o) and the quality factor (Q) can be set orthogonally by adjusting the circuit components. The ω o can also be controlled electronically by varying the transconductance value of OTAs. The simulation results are performed to confirm the presented theory. © 2011 IEEE.