Current-Mode and Transimpedance-Mode Biquadratic Filter Circuit Using Five OTAs

A current-mode and transimpedance-mode biquadratic filter circuit with single current input terminal using five operational transconductance amplifiers and two grounded capacitors is presented. The proposed circuit can realize current-mode highpass, bandpass and lowpass responses, simultaneously. The current-mode notch and allpass responses can be obtained by interconnection of relevant output currents. Moreover, the transimpedance-mode highpass, bandpass and lowpass filters can also be obtained, simultaneously, from the proposed circuit. The resonance angular frequency and quality factor can be orthogonally adjusted.