Understanding MOSFET Threshold Voltage

Understanding MOSFET Threshold Voltage

Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) are fundamental components in modern electronic circuits, serving as switches and amplifiers. Among their critical parameters, the threshold voltage (V TH ) plays a pivotal role in defining when the MOSFET turns from the "off" state to the "on" state. This article explores the MOSFET threshold voltage in detail — its physical meaning, mathematical formulation, calculation methods, example problems, and practical implications. What is MOSFET Threshold Voltage? The threshold voltage of a MOSFET is the minimum gate-to-source voltage (V GS ) required to create a conducting channel between the drain and source terminals. Below this voltage, the MOSFET remains off, and above it, the device allows significant current flow. In simpler terms, V TH is the voltage level at which an inversion layer forms at the semiconductor-oxide interface, enabling current conduction. Types of Threshold Voltage Enhancement Mode MOSFETs: …