Operational Transconductance Amplifier (OTA) based Schmitt Trigger without passive elements

The paper reports a current-tunable Schmitt trigger with tunable hysteresis using only Operational Transconductance Amplifiers (OTAs). The Schmitt trigger circuit does not use passive elements which is suitable for an integrated circuit realization. The threshold voltages and the output saturation levels can easily be adjusted. Simulation results obtained using LTSpice are used to verify the functionality of the proposed circuit.