Electronically tunable voltage-mode universal filter with two inputs four outputs employing single-ended OTAs and grounded capacitors

This paper presents a new voltage-mode electronically tunable universal filter with two-input four-output using six single-ended operational transconductance amplifiers (OTAs) and two grounded capacitors. The proposed circuit provides lowpass, bandpass and highpass voltage responses at a high impedance input terminal, which enable easy cascadability. The filter also offers an electronic control of the natural frequency through adjusting the bias current of the OTAs. The active and passive sensitivities are low. The performances of the proposed filter are simulated to confirm the presented theory.