Quadrature oscillators using two CFOAs and four passive components

Abstract

Two new quadrature sinusoidal oscillators using current-feedback operational amplifiers (CFOAs) as an active building block are proposed. The proposed circuits use two CFOAs with the minimum number of passive elements, namely two resistors and two grounded capacitors. The use of only grounded capacitors makes the proposed circuits ideal for integrated circuit implementation. Both proposed circuits offer the advantages of orthogonal control of the oscillation condition and oscillation frequency, availability of two quadrature sinusoidal voltage outputs and low active and passive sensitivity performances. The HSPICE simulation and experimental results are provided to demonstrate the theoretical analysis.