Bipolar Junction Transistors

A semiconductor device that controls current. The function is to amplify weak signals into electrical signals with larger amplitude values, and also used as contactless switches.
Bipolar transistors have a current amplification effect, which essentially controls the large change in collector current with a small change in base current. This is the most fundamental and important characteristic. We will Δ Ic/ Δ The ratio of Ib is called the current amplification factor of the transistor, denoted by the symbol“ β” Represent. The current amplification factor is a fixed value for a certain transistor, but it will also change to a certain extent as the base current changes during transistor operation.