Single VDBA-based phase shifter with low output impedance

This paper proposes a realization of an electronically tunable voltage-mode phase shifter section using a single voltage differencing buffered amplifier (VDBA) as an active component, together with one floating capacitor and one grounded resistor as passive components. The proposed circuit is efficient of providing an electronic control of the natural angular frequency (fflb) through the transconductance gain of the VDBA. It also possesses low output impedance, which makes it conveniently cascadable. PSPICE simulation results, including frequency response and transient analysis, are incorporated to verify the theoretical analysis.