DXCCII based electronically tunable current-mode universal filter

A current-mode biquad filter employing dual-x second generation current conveyor as active element is presented. The proposed circuit has one input and three outputs and can simultaneously realize low-pass, band-pass and high-pass responses. The biquad employs three DXCCIIs, three triode MOSFETs and two grounded capacitors. It avails tunability via control voltages with aid of triode MOSFETs. PSPICE simulation results verify to theory. The circuit proposed provides to the IC designer new possibilities to realize IF blocks in ICs for several communication systems such as GSM and radio receivers.