Puolijohdekapasit

Puolijohdekapasit, also known as bipolar junction transistors (BJTs), are fundamental components in electronics, serving as current-controlled current sources. They consist of three layers of semiconductor material: a p-type layer sandwiched between two n-type layers, or vice versa. The middle layer is known as the base, while the outer layers are the emitter and collector. When a small current is applied to the base, a much larger current flows from the collector to the emitter, making the BJT an amplifier. BJTs are widely used in various applications, including radio frequency (RF) circuits, power amplifiers, and digital logic circuits. They are available in different configurations, such as npn and pnp, depending on the arrangement of the semiconductor layers. The performance of a BJT is characterized by parameters like current gain (β), maximum collector current (Ic,max), and breakdown voltage (BVceo). BJTs are known for their high current gain and ability to handle large currents, making them suitable for power amplification and switching applications. However, they are sensitive to temperature changes and require careful biasing to ensure proper operation.