Fractional-Order Relaxation Oscillators Based on Op-Amp and OTRA

This paper introduces closed formulas of two topologies of fractional-order relaxation oscillators. One of these topologies is based on Operational Amplifier (Op-Amp) and the other one depends on Operational Operational Trans-Resistance Amplifier (OTRA). Special cases for each topology are also provided. The advantage of these designs comes from the added extra degree of freedom presented by the fractional-order α. Matsuda’s approximation of sα is used to implement fractional-order capacitors. Also, experimental work is included to verify the theoretical results.

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