Electronically Tunable Current-Mode Universal Filter Employing Only Plus-Type Current-Controlled Conveyors and Grounded Capacitors

A new current-mode current-controlled three-input single-output universal filter, which employs only five plus-type second-generation current-controlled current conveyors (CCCIIs) and two grounded capacitors, is presented in this paper. The proposed configuration provides lowpass, bandpass, highpass, bandstop, and allpass current responses at a high impedance terminal, which enables easy cascadability of the circuit. The filter also offers independent electronic control of the natural frequency ω_o and the quality factor Q through adjusting of the bias current of the CCCII. Derived analytical expressions for the filter parameter deviations due to CCCII nonidealities are also included. PSPICE simulation results are performed to confirm the theoretical analysis.