Realisations of single-resistance-controlled quadrature oscillators using a generalised current follower transconductance amplifier and a unity-gain voltage-follower

Abstract

This article presents realisations of single-resistance-controlled- oscillators (SRCOs) using the recently proposed modern active building block (ABB), namely the generalised current follower transconductance amplifier (GCFTA) and unity-gain voltage-follower (UGVF). The SRCO is made using reduced number of components: one GCFTA and one UGVF as the ABBs, two resistors and two grounded capacitors. The circuit offers the advantage of non-interactive control of condition of oscillation and frequency of oscillation and enjoys low active and passive sensitivities. The circuit is also capable of providing two quadrature voltage outputs. PSPICE simulations have been carried out using the bipolar implementation of the circuits. The simulation results validate the theoretical analysis. © 2010 Taylor & Francis.