NPN and PNP Transistor

The NPN and PNP transistors are two of the most important types of transistors that have been used in electronic circuits. These transistors work together to amplify an electrical signal, which can be emitted from a power source or captured by a detector.  In addition to amplifying and filtering the signal, these two types of transistors are also known for their ability to create switching action and input-output levels, as well as generate current. The NPN process requires the creation of electric fields when metals connect across each other on either side of the circuit board; this is how it creates input voltage levels for a circuit where it is being used.

What is an NPN Transistor?

The NPN transistor is usually used for amplification. This involves the ability to amplify a power voltage by forming an electric current inside of it. The process that this transistor follows is known as amplification; in this process, the input voltage can be amplified, and then passed through to the next stage of components, where the output is applied. The NPN transistor requires two external connections and two internal connections; two of these are electrons connected across each other at either end of the circuit board.

Features of NPN Transistor:

• It can amplify electrical current
• It can be used as a static switch in a circuit
• It has two inputs and two outputs
• It works in both alternating and direct current circuits
• It is made of semiconductor silicon material
• The electric field is formed by the two diodes placed on either side of the transistor

What is a PNP Transistor?

The PNP transistor follows the same process as the NPN transistor, only instead of using electrons, it uses holes. The PNP transistor is typically used in a switching circuit because it does not require amplification or current. You can connect this type of transistor onto the circuit board, and then have an output that can be applied externally. It requires three external connections and two internal connections; one of these is holes connected across each other at either end of the circuit board.

Features of PNP Transistor:

• It can create a switching effect
• It can be used in a circuit that does not require current
• It has two inputs and one output
• It works on both alternating and direct current power sources
• It is made of semiconductor silicon material
• It works in a way similar to the NPN transistor
• While the NPN turns on due to the presence of electrons, the PNP turns on due to the presence of holes

Both transistors do essentially the same thing in terms of amplifying electrical signals. The difference is that with an NPN transistor, you need an external voltage source as well as an external ground.

The difference between NPN and PNP Transistors:

There are many differences between these two transistors, some of which are:

1) The PNP transistor has a high input impedance, whereas the NPN transistor has a low input impedance.

2) The PNP transistor will require more current to operate, whereas the NPN transistor will require less.

3) The NPN transistor needs an external ground to work on, whereas the PNP transistor does not need an external ground.

4) The PNP transistor is easier to work with than the NPN, because it converts its input voltage into output voltage in an easier way than the NPN.   

Conclusion

While both of these transistors have their differences, they are overall very similar in many ways. The main difference is the PNP transistor needs an external ground, while the NPN transistor does not need an external ground. Both of these transistors can be used in switching circuits and amplifiers, but the NPN will require more current than the PNP. The NPN also has a low input impedance, whereas the PNP has a high input impedance. You can utilize both transistors to amplify electrical signals and create switching systems within your circuit board. Based upon their differences, different circuits have different benefits to using one over another; depending on what you are trying to do, you may find yourself choosing between one or the other to get your desired results.