Is BJT bipolar or unipolar?

BJT is called bipolar because the current in a BJT flows due to both electron and hole carriers, whereas the current in a Field Effect Transistor (FET) flows due to either electron carriers for N-type FET or hole carriers for P-type FET, hence they’re called unipolar transistors.

What are the basic parts of a bipolar transistor?

The Bipolar Transistor basic construction consists of two PN-junctions producing three connecting terminals with each terminal being given a name to identify it from the other two. These three terminals are known and labelled as the Emitter ( E ), the Base ( B ) and the Collector ( C ) respectively.

What is BJT and its types?

BJTs are of two types namely NPN and PNP based on doping types of the three main terminals. An NPN transistor consists of two semiconductor junctions that have a thin p-doped anode region and PNP transistor also consists of two semiconductor junctions that have a thin n- doped cathode region.

What do you need to know about bipolar junction transistors?

The bipolar junction transistor shown in Figure below (a) is an NPN three layer semiconductor sandwich with an emitter and collector at the ends, and a base in between. It is as if a third layer were added to a two layer diode. If this were the only requirement, we would have no more than a pair of back-to-back diodes.

Which is the typical cross section of a NPN transistor?

The typical cross section of a planar NPN transistor is shown in figure 8.3.1. An NPN transistor can be viewed as two PN junction diodes with a very thin shared anode, P layer. In typical operation, the base-emitter junction is forward biased and the base collector junction is reverse biased.

What is the insulated gate bipolar transistor ( IGBT )?

IGBT Fundamentals. The Insulated Gate Bipolar Transistor (IGBT) is a minority-carrier device with high input impedance and large bipolar current-carrying capability. Many designers view IGBT as a device with MOS input characteristics and bipolar output characteristic that is a voltage-controlled bipolar device.

How many types of transistors are there in the world?

There are four transistor types that correspond to these basic active device models. The schematic symbols for these are shown in figure 8.2.1. The n-type current controlled device is the NPN Bipolar Junction Transistor (BJT). The p-type current controlled device is the PNP BJT.