Realizations of simple fractional-order capacitor emulators with electronically-tunable capacitance

A novel resistorless topology for implementing fractional-order capacitor emulators, based on the employment of Operational Transconductance Amplifiers (OTAs) as active elements, is presented in this paper. The benefits of this topology are its simplicity in terms of component count, compared to other existing topologies in the literature, in addition to its electronic tunability. The performance of the presented topology is evaluated using Cadence and the 0.35 μm CMOS process Design Kit from Austria Mikro Systeme. Experimental results using commercial OTA chips are also provided, where the emulation of fractional-order capacitors is demonstrated. © 2019 Elsevier B.V.