Novel first-order all-pass filter applications of z-copy voltage differencing current conveyor

Abstract

The application of z-copy voltage differencing current conveyor (ZC-VDCC) in simple and interesting first-order allpass sections has been studied in the present paper. The solutions presented here have presumptions for direct electronic control. Some of proposed circuits offer curious possibilities of control. Electronic controllability of the VDCC allows simultaneous zero and pole frequency adjusting, separated zero or pole frequency adjusting or migration of zero from left half plane to right half plane of complex space. Behavioral models of VDCC based on commercially available devices are proposed and selected type of all-pass section was verified by simulations and also by measurements. Results of simulations, experiments, and theoretical proposal are compared. Experiments confirm workability of proposed behavioral equivalent circuit in bandwidths to units of MHz.