Example: the micro-alloy diffused transistor of Philco. Diffusion Transistor: These are a type of BJT that is created via dopant diffusion into a semiconductor substrate.It has avalanche-mode operations that change between high currents in less than nanoseconds. Avalanche Transistor: It is a type of Bipolar Junction Transistor that processes the region of collector-current/collector-to-emitter voltage area.Some other major types of transistors are – FETs can be further classified as JFETs and MOSFETs.Ĭlassification of Metals, Conductors, and Semiconductors.As a result, FETs draw extremely little current from the power source of a circuit.The current is very low if the impedance is high.(The current is inversely impacted by the value of the circuit's resistance, according to Ohm’s Law.) Due to their high input impedance, these types of transistors only receive a little amount of current.Field-Effect transistors have extremely high input impedances, ranging from a few mega ohms (M) to very high values.A voltage applied to the transistor's gate controls the current flow from the source to the drain. FETs are voltage-controlled bipolar transistors that are different from bipolar transistors. Field-Effect Transistors (FETs)įield-Effect Transistors are those types of transistors that are made up of three regions: the gate, source, and drain. Read More: Difference Between NPN and PNP Transistors 2. NPN transistors are currently the most widely used BJTs because electron mobility is greater than hole mobility in them.In a transistor, a low current supply at the base terminal can result in a large amount of current flowing from the emitter to the collector.The current flow within the base terminal of the transistor is formed by electrons flowing from the emitter terminal to the collector terminal.The majority of charge carriers in an NPN transistor are electrons, whereas the minority are holes.

PNP Transistor consists of two n-type semiconductor layers separated by a thin p-type semiconductor layer.

When the base terminal is pulled to LOW in comparison to the emitter terminal, the transistor will switch on.

The current flows from the emitter terminal to the collector terminal in this transistor.

The majority of charge carriers in these transistors are holes, whereas the minority are electrons. A thin n-type semiconductor layer separates these materials. In these types of transistors, there are two p-type semiconductor materials.

NPN and PNP are the two main types of bipolar junction transistors.īipolar Junction Transistor i) NPN Transistor.A little current flowing from the emitter to the collector region of the transistor causes a considerably bigger current to flow from the base to the emitter.Different from FET transistors, bipolar junction transistors are current-controlled devices. Some of these are –īipolar Junction Transistors are those types of transistors that are made up of three regions: the base, collector, and emitter. There are many types of transistors that can be classified on the basis of their application.

Transistor meaning