The classical complementary metal–oxide–semiconductor (CMOS) Schmitt trigger (ST) circuit operating in strong inversion has been used as a basic building block in electronics since the 70s. However, no appropriate analytical models for determining the hysteresis threshold voltages have been presented. In this paper, we review the classical CMOS ST formulation for operation in strong inversion and introduce a new model for calculating the hysteresis window. In order to validate the approximations employed in this work, we measured the hysteresis curve for several combinations of transistors available in the popular off‐the‐shelf CD4007 and resorted to simulation in a 180‐nm technology for the specific purpose of measuring the ST window in terms of the transistors aspect ratios. Numerical, experimental, and simulation results corroborate the approximations employed in this research to derive simple expressions for the hysteresis threshold voltages.

中文翻译：

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CMOS施密特触发器的经典公式不足

自上世纪70年代以来，经典的互补金属氧化物半导体（CMOS）施密特触发器（ST）电路以很强的反转能力工作，已被用作电子产品的基本组件。然而，没有提出用于确定滞后阈值电压的适当分析模型。在本文中，我们回顾了用于强反演的经典CMOS ST公式，并介绍了一种用于计算磁滞窗的新模型。为了验证在这项工作中采用的近似值，我们测量了流行的现成CD4007中可用的几种晶体管组合的磁滞曲线，并针对测量ST窗的特定目的采用了180 nm技术进行仿真。就晶体管的长宽比而言。数值，实验，