The operation of a p-np transistor is identical to that of an n-p-n transistor, except that the bulk of charge carriers are holes rather than electrons. As a result of KCL, the base current is quite low compared to the emitter and collector currents.Įlectrons make up the majority of charge carriers in this system. The collector current is formed when the remaining huge number of electrons traverse the reverse-biased collector junction. This is the base current, which flows due to electron and hole recombination (Note that the direction of conventional current flow is opposite to that of the flow of electrons). Because the base is narrow and lightly doped, it has a tiny number of holes as a result, around 2% of the electrons from the emitter recombine with the holes in the base region and flow out of the base terminal. The electrons flow from the emitter to the base due to the forward bias at the BE junction, which reduces the barrier potential. Compared to the CB junction, the BE junction’s depletion region is narrower. The BE junction is forward biased, but the CB junction is reversed biased, as seen in the figure of an n-p-n transistor biased in the active area (see transistor biasing). BJTs are well-suited to low-current applications such as switching. The operating principles of these transistors are nearly identical, with the primary differences being in biasing and power supply polarity for each kind. P represents positive, and most charge carriers in the PNP transistor are holes, whereas N is negative, and most charge carriers in the NPN transistor are electrons. The charge carriers are the key distinction between BJTs and MOSFETs. NPN and PNP transistors are the two types of transistors. The P-junction and N-junction are the names of the two locations. The emitter, base, and collector are the three terminals on this transistor.Ī BJT is a silicon piece with three regions and two junctions. The current at the base terminal determines the operation of a BJT transistor in its most basic form. The BJT is a current-controlled device in which the base terminal or emitter terminal’s o/p function of the base terminal’s current. A bipolar junction transistor is a type of semiconductor device that was formerly used to replace vacuum tubes.
0 Comments
Leave a Reply. |