Versatile voltage-mode quadrature oscillator circuit using DDCCs

This paper presents a new versatile voltage-mode quadrature oscillator circuit using three differential difference current conveyors, two grounded capacitors and three grounded resistors. Unlike the previously reported quadrature oscillator, the proposed circuit can realize a quadrature oscillator and a universal filter without changing the circuit topology. When the circuit works as a quadrature oscillator, it provides the following advantages: the oscillation condition and oscillation frequency are orthogonally controllable and the circuit enjoy interactive frequency control. Alternatively, when the circuit functions as a universal filter, it can realize low-pass, band-pass, high-pass, band-stop and all-pass voltage responses. The parameters ω_o and Q can be independently controlled. Simulation results verifying the theoretical analysis are also included.