It consists of two PN Junctions coupled back-to-back with a common middle layer.
The Bipolar Junction Transistor or simply BJT is a three-layer, three terminal and two junction semiconductor device. There are two main families of Transistors: Bipolar Junction Transistors (BJT) and Field Effect Transistors (FETs). This article mainly concentrates on the switching action of the transistor and gives a brief explanation of transistor as a switch. You can find Transistors in both digital and analog domains as they are extensively used for different application usage like switching circuits, amplifier circuits, power supply circuits, digital logic circuits, voltage regulators, oscillator circuits and so on. As one of the significant electronic devices, transistor has found use in enormous range of applications such as embedded systems, digital circuits and control systems. Transistors is a three-layer, three-terminal semiconductor device, which is often used in signal amplification and switching operations.
