What is the difference between bjt and transistor

In the PNP transistor, P stands for positive and the majority charge carriers are holes whereas in the NPN transistor, N stands for negative and the majority charge carriers are electrons. The operating principles of these transistors are practically equal and the main difference is in biasing as well as the polarity of the power supply for each type.

BJTs are apt for low current applications like switching purposes. The working principle of a BJT involved the use of Voltage between the two terminals such as base and emitter to regulate the flow of current through the collector terminal.

For instance, the configuration of a common emitter is shown in the figure below. So this transistor is a current controlled device. Here, the drain current is controlled by the voltage of the gate terminal Therefore, these transistors are voltage-controlled devices.

These transistors are available in 4 different types such as P-channel or N-channel with either an enhancement mode or depletion mode. When more voltage is applied to the gate terminal, then the conductivity of this device is good. The oxide layer presents, among the two terminals such as source and drain.

The deflection region occupied by the bound —Ve charges which are associated with the acceptor atoms. But before selecting the BJT or MOSFET, there are several factors that need to consider like the level of power, efficiency, drive voltage, price, speed of switching, etc.

A Bipolar junction transistor, commonly known as BJT, by its construction, looks like two p-n junction diodes connected back to back. It is a three-terminal Emitter, Base, collector , current controlled device. In NPN transistors, a thin layer of p-type semiconductor is sandwiched between two n-type semiconductors whereas, in PNP transistors, a thin layer of n-type semiconductor is sandwiched between two p-type semiconductors. The current flow is due to the flow of majority as well as minority charge carriers.

The current flow is due to the flow of majority charge carriers. Current flow is due to both electrons and holes , therefore name bipolar transistor. The current flow is due to either electrons or holes, therefore, named unipolar transistor. There are two types of BJT i. BJT construction is comparatively easier. The FET construction is comparatively difficult.

The 3 terminals are named emitter, base and collector. There are no PN junctions. It is a current-controlled current device. It is a voltage-controlled current device. The B-E junction is forward biased and the B-C junction is reversed biased. The Gate voltage is reversed biased while the drain voltage is maintained higher than the source.

The BJT has very simple biasing. The FET biasing is a little difficult. The emitter and base cannot be interchanged or swapped. The drain and source can be interchanged since the drain should be more positive. BJT has a very high gain.

FET has a comparatively low gain. The input impedance is very low in the range of 1K ohms. The input impedance is very high in the range of M ohms. The output impedance is very high thus high gain. The output impedance is very low thus low gain. There is current flow at its base terminal. There is negligible current at its base terminal.

BJT has an offset voltage requirement. FET does not require offset voltage. Dependent on input current, It consumes high input energy at normal operation. The main criteria of these transistors is to control the flow of current that passes through one channel by making the variations in the intensity of the currents that are very smaller which flows through the second channel.

BJT stands for bipolar junction transistor. It consists of one p-type and both n-types referred to as n-p-n or one n-type and both p-types referred to as p-n-p.

Generally the ideology behind this is two diodes with the p-n junction can be connected in such a way that a bipolar junction has been formed.