Voltage Differencing Gain Amplifier-based Sinusoidal Quadrature Oscillator Using Only Two Grounded Capacitors

Background: This article describes the circuit construction of the sinusoidal quadrature oscillator using two Voltage Differencing Gain Amplifiers (VDGAs) as active devices. Methods: Since the presented oscillator circuit uses only two external grounded capacitors as passive elements, it is quite suitable for monolithic integration point of view. The condition of oscillation and the frequency of oscillation are non-interactive, and can be controlled electronically by tuning two separate biasing currents. Non-ideal analysis and sensitivity performance are also discussed. Results: The feasibility of the designed oscillator is justified by the PSPICE simulation results based on TSMC 0.35-mu m CMOS process parameters. Conclusion: The effects of the VDGA non-idealities on the proposed circuit are also provided, and the computer simulations based on TSMC 0.35-mm CMOS model parameters are included to evaluate the performance of the circuit.