What is the function of a MOSFET?

A MOSFET, or Metal-Oxide-Semiconductor Field-Effect Transistor, primarily functions as an electronic switch or amplifier. Its ability to control current flow makes it versatile in various applications, particularly in digital circuits and signal processing. When used as an amplifier, the MOSFET can amplify signal voltage variations, making it crucial in analog applications where signal integrity is important.

The MOSFET operates by varying the voltage applied to its gate terminal, which in turn alters the current flowing between the drain and source terminals. This feature allows for precise control over the output current in response to changes in input voltage, facilitating signal amplification.

In contrast, other options like storing energy or rectifying voltages do not fully encapsulate the primary role of a MOSFET. While certain MOSFET configurations can participate in energy storage or be used in rectifying circuits, these are not the foundational functions of a MOSFET itself. Instead, its most salient capability lies in controlling current and amplifying signals, making it an essential component in modern electronic devices.