Low-frequency quadrature sinusoidal oscillators using current differencing buffered amplifiers

This paper proposes new realizations of low-frequency quadrature sinusoidal oscillators using CDBA (current differencing buffered amplifier) as the active building block (ABB). The proposed circuits employ reduced number of components, namely two CDBAs, four (or five) resistors and two true/virtually grounded capacitors. The oscillators provide two quadrature voltage outputs and the condition of oscillation (CO) and the frequency of oscillation (FO) are independently controllable. Low frequency generation is enabled by the presence of difference term in the numerator of FO. The non-ideal analysis and sensitivity study of the circuits have been carried out and the circuits exhibit satisfactory sensitivity performance. SPICE simulation results are included that validate the working of the circuit.