Resistorless current-mode quadrature sinusoidal oscillator using CDTAs

A circuit technique for realizing a current-mode quadrature sinusoidal oscillator using current differencing transconductance amplifiers (CDTAs) as active components is presented in this paper. The proposed circuit employing only three CDTAs and two grounded capacitors can provide two quadrature sinusoidal current outputs with 90° phase difference. The oscillation condition and the oscillation frequency (ωo) of the proposed circuit can be electronically and orthogonally tuned. Simulation results with PSPICE are used to confirm the presented theory.