What are PNP and NPN?

What are PNP and NPN?

A positive voltage is applied to the collector terminal of an NPN transistor to cause current to flow from the collector to the emitter. A positive voltage is applied to the emitter terminal of a PNP transistor to cause current to flow from the emitter to the collector. The direction of current flow between these two terminals is determined by the type of transistor involved.

In general, transistors can be divided into two major categories based on the polarity of voltage that will cause current to flow between the collector and emitter terminals. These are N-type transistors and P-type transistors. An N-type transistor will conduct current from a negative source voltage to a positive drain voltage, while a P-type transistor will conduct current from a positive source voltage to a negative drain voltage. This is true regardless of the polarity of the voltage applied to the gate (control) electrode.

In practice, however, it is not possible to make both the collector and emitter terminals of a single transistor negatively charged with respect to ground. This is because any charge that might be present on these terminals would attract electrons from outside the transistor, which cannot happen if they are already inside the transistor. Thus, only one terminal of a bipolar transistor can be negatively charged while the other terminal is positively charged. This means that an NPN transistor cannot be used as a switch if both its collector and emitter are negative with respect to ground.

What is the symbol for the NPN and PNP transistors?

NPN vs. PNP transistors

NPN TransistorPNP Transistor
Symbol
Collector-emitter voltagePositiveNegative
Emitter arrowPointed outPointed in

What is the PNP and NPN junction?

What exactly are NPN and PNP? A bipolar junction transistor is composed of three silicon components. A piece of P-type silicon (the base) is sandwiched between two pieces of N-type silicon in an NPN transistor (the collector and emitter). The layers' types are reversed in a PNP transistor. Each layer has three key roles to play: as a conductor, as a semiconductor, and as a dielectric.

The base region must be wide enough so that enough electrons can move into it when the transistor is on. If it is too narrow, then too few electrons will be available to flow through it when the transistor is on. This is called "shorting the base" because you have only one side able to conduct electricity. As soon as you short the base, the transistor will no longer operate properly; instead of being turned on by the voltage across its emitter and collector, it will be forced off by these same voltages.

The collector needs to be wide enough to collect enough electrons from the environment. Like the base, the collector can also be "shorted" by connecting its emitter and base together. Once again, the transistor will no longer function properly; this time, it will never be able to turn off. All transistors need some form of bias to ensure that they don't stay on all the time.

What does NPN stand for in transistors?

The abbreviations for npn and pnp transistors are as follows: With changing doping concentrations, NPN employs n-type semiconductor material as an emitter, p-type semiconductor material as the base, and n-type semiconductor material as the collector area. The symbol for npn transistors is shown below.

Similarly, pnp transistors employ p-type semiconductor material for the emitter, n-type semiconductor material as the base, and p-type semiconductor material as the collector area. The symbol for pnp transistors is also shown below.

NPN and PNP transistors are the most common types of bipolar transistors. A bipolar transistor is a three-terminal electronic component that can be used as a switch or amplifier. Bipolar transistors were first developed in the 1950s and have been widely used since then in radio frequency (RF) circuits such as antennas, wireless communication devices, and radar systems.

In conclusion, NPN stands for npn transistors, and PNP stands for pnp transistors.

About Article Author

Max Rose

Max Rose is an educator and writer. He loves to help people understand complex topics in easy to understand ways. He also enjoys sharing his own personal stories about what it's like being an educator in this field.

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