Realization of voltage-mode and current-mode biquad filters using current feedback amplifiers

摘要

This paper presents two each of voltage-mode (VM) and current-mode (CM) universal biquad filtering topologies constructed around current feedback amplifier (CFA). The VM configurations are based on lossless integrator loops. One of the CM topologies has three inputs and one output and the other with a single input and three outputs. Both the VM configurations and one of the CM circuits realize lowpass notch (LPN) and highpass notch (HPN) functions in addition to all the generic filtering functions while the other CM circuit realize three basic filtering functions simultaneously. The filter parameters are orthogonally adjustable and enjoy low sensitivity figures. The circuits have been simulated using personal computer simulation program with integrated circuit emphasis (PSPICE) and simulation results are found to be in conformity with the theoretical values.