Transistor BJT – the most basic elements of discrete
Bipolar transistor barbed wire was invented in December 1947 at Bell Telephone Laboratories John Bardeena and Walter Brattaina, working under the guidance of William Shockleya. The next iteration of the project, that is, bipolar transistors złączowy (BYUT), it was invented Shockleya year later. This opened a huge opportunity in electronics. Transistors replaced vacuum tubes. From them better, smaller and more energy efficient, but the technology of production of such items has changed dramatically since their invention to this day. Still remained, however, an integral part of any electronic equipment. Transistors made it possible not only to reduce the size of the radios or TVs, but has also permitted the emergence of integrated circuits, which contain in their structure often millions of transistors.
How are the bipolar transistors
The bipolar transistor consists of three differently doped semiconductor regions emitter, base and collector. These regions are doped P-type or N and arranged alternately. Each semiconductor region is connected to the terminal, respectively, labeled emitter (e), base (B) and collector (C). The base is located between the emitter and the collector and is made of slightly domieszkowanego material with a high resistance. The collector surrounds the emitter area, which is almost impossible to get electrons wstrzykiwanych for the region's asset without their collecting, and the obtained gain value in the system common framework is very close to unity and, therefore, gives tranzystorowi a large gain value in the system common header.
The bipolar transistor Elements NPN and PNP differences in the structure and action
The stacking order of layers of P and N in tranzystorze bipolarnym determines its appearance and actions. BYUT is available in two types or polarnościach, known as PNP and NPN. NPN transistor contains two semiconductor connector that share a thin P-doped region in turn, the PNP transistor contains two semiconductor connector that share a thin region doped with N. n-p-N is one of the two types of bipolar transistors. Consists of a layer of semiconductor domieszkowanego P between the two layers domieszkowanymi N. a Small current, a part of the base is enhanced to generate a large collector current and emitter. When there is a positive potential difference measured from the base to the emitter, the transistor is turned on. The PNP transistors are built exactly the opposite way. They also have the opposite effect. They are active when there is no voltage.