Digitally Programmable Voltage-Mode Universal Biquadratic Filter

A single input multi-output voltage mode universal biquadratic filter has been presented. The circuit incorporates digital programmability employing three plus-type differential voltage current conveyors (DVCCs), two grounded capacitors and three resistors. The circuit exhibits high input impedancerealizes all the standard filter functions having orthogonal control of cut-off frequency and quality factor. Parameter tunability is achieved by the use of a 3-bit digital control word. The proposed circuits are amenable for monolithic integration by virtue of the fact that only grounded capacitors are employed. Circuit simulations using PSPICE are in perfect agreement with the theoretically predicted results.