Power transistors are semiconductor devices designed to handle high current and high voltage levels, making them suitable for controlling and amplifying large amounts of electrical power. They are primarily used as electronic switches or power amplifiers in power electronics and control circuits.
Unlike small-signal transistors, power transistors are built with robust structures and heat-dissipation capabilities, often requiring heat sinks to manage thermal stress. They are available in different types, including power BJTs, power MOSFETs, and IGBTs, each chosen based on switching speed, efficiency, and power handling needs.