Current Conveyor-Based Square/Triangular Waveform Generators With Improved Linearity

Two second-generation current conveyor (CCII+)-based resistance-capacitance (RC) square/triangular waveform generators, which have been derived from their voltage-mode op-amp-based schemes, with independent control of frequency are presented in this paper. Each configuration consists of two positive second-generation conveyors (CCII(+)-ldquoArdquo and CCII(+)-ldquoBrdquo), three resistors, and one floating capacitor that is responsible for better linearity. The frequency of the waveform generators can independently be adjusted with any passive device. The circuits were built with commercially available current feedback operational amplifiers (AD844) and passive components used externally and tested for waveform generation and tunability. The measured results included in the paper show excellent linear variation of frequency as compared with existing reported configurations over the range from 25 Hz to 260 kHz. The configurations that are suitable for very large scale integration (VLSI) realization find application in capacitive and resistive sensors and in neuro-fuzzy systems.