A high-speed differential CMOS Schmitt trigger with regenerative current feedback and adjustable hysteresis

This paper presents a brief overview of Schmitt triggers and proposes a new differential current-feedback Schmitt trigger. The hysteresis of the proposed Schmitt trigger is generated using regenerative current feedback and can be adjusted by varying the current of the regenerative feedback network. The center of the hysteresis can also be adjusted by varying the common-mode input voltage. The proposed Schmitt trigger has the characteristics of current-mode circuits, making it particularly attractive for low-voltage high-speed applications. The proposed Schmitt trigger has been designed in TSMC-0.18 mu m 1.8 V CMOS technology and analyzed using Spectre from Cadence Design Systems with BSIM3V3 device models. Simulation results are presented.