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2n222 Pinouts: A Complete Guide and More!

Many electronic devices use transistors, and the 2n2222 pinouts transistor is just one among the huge transistor family. The 2n2222 transistor can handle a higher amount of current than other transistors, and it can switch a load current of 800mA, which is often high compared to other transistors.

In this article, we will learn more about the features of the 2n2222 transistor, its alternatives, and more. It is essential because it will enable you to figure out connections of the 2n2222 transistor in your circuits

Let's start!




2n2222 is an NPN bipolar junction transistor. Importantly, its uses are for analog frequency amplification and switching applications. The 2n2222 transistor amplifies signals by receiving an analog signal through the collectors, and the base gets another signal. For instance, this analog frequency could be a human voice. The TO-18 package encloses the main functional area of the 2N-2222 transistor. Moreover, its small size and efficiency make it the most preferred transistor in many electronic devices.


2n2222 pinout diagram


SOURCE: Wikimedia Commons

SOURCE: Wikimedia Commons


Pin Configuration Description


The 2n2222 transistor consists of 3 pins. Consequently, the transistor pins either turn it on or off. These pin configurations descriptions are below;

  1. Firstly, pin #1- referred to as the emitter
  2. Second, pin #2- simply the base
  3. Thirdly, pin #3- known as the collector.


Pin Function

2N2222 pinout diagram

 (2N2222 pinout diagram)


2. 2n2222 NPN transistor electrical features


The key features of a 2n2222 NPN transistor are;

  • Gain (hFE) : 100-300
  • Collector-emitter saturation voltage (Vce sat): 0.3-0.5 volts
  • Collector current (Ic): 0.1 amps
  • DC Current gain (hfe): 60-150
  • Collector power dissipation (Pc): 0.5 watts
  • Frequency response: 0-1000 MHz
  • Operating temperature (Tj), °C: -55 to +150
  • Storage temperature (Tstg): -55 to +150
  • Thermal resistance junction-to-ambient air (Rja): 80°C/W
  • The Thermal resistance junction-to-case (Rjc): 90°C/W
  • Thermal resistance junction-to-ambient air (Rja): 80°C/W
  • Collector emitter breakdown voltage (V(beo)ce): 50 volts
  • DC current gain-collector to emitter (hfe): 100-300
  • Collector-emitter saturation voltage (Vce sat): 0.5 volts
  • Power transistor dissipation (Tc): 1 watt
  • Collector-emitter voltage (Vce): 0.3 volts



( Transistors)


3. Alternative options and equivalents


There are many different types of transistors in the electronics world. For instance, the 2n2222 transistor has alternative options, such as the MPSA42 and the 2N3906. On the other hand, its equivalents are the KTN2222, BC637, BC547, PN2222, MPS2222, KN2222, 2N2907and 2N3904.

The 2n2222 transistor is equivalent to the bc547 transistor but slightly different because the pin configuration is reverse in bc547 transistor pinouts.

A feature difference between the 2n2222 and the bc547 is that the 2n2222 transistor allows a collector current of up to 800mA. However, bc547 cannot power up to 800mA. Consequently, the power dissipation of a 2n2222 is 652mW and can power larger loads than the bc547.


2n222 pinouts--Different types of transistors

(Different types of transistors)


4. 2n2222 Package Introduction


Most importantly, the 2n2222 transistor package uses the TO-18 package, which is a design for transistor metal case style. In addition, the TO-18 package style of the casing is more expensive compared to the TO-92 package.

Transistors using 1,2, or 3 leads (not more than three) use the 3-lead TO-18 package. It is so because examples of LED, diodes, and photodiodes may use only two leaders. Light-emitting or light-sensitive diodes have a transparent window or parabolic reflector in the top of their case rather than a sealed flat top.


2n222 pinouts--Integrated circuit chip with a TO-18 package

 (Integrated circuit chip with a TO-18 package.)


5. Basic 2n2222 Example Circuits


Here we discuss examples of NPN transistors connected in circuits. We have a simple LED controlling model with a switch and another important example to help you understand better!


2n222 Pinouts--An LED Controlling Circuit


This circuit connects the base terminal and collector terminal to the power source through a 220ohm resistor.


2n222 pinouts--An LED Controlling Circuit

(An LED Controlling Circuit)


It is an LED controlling circuit that will not work without the 10kΩ resistor. In addition, if you use it, the switch won't turn on because of the low current passing. However, all should be well with this smaller value for resistors like a 220-ohm resistor between terminals and a 5 volts logic signal at base input (on/off)!


2n222 Pinouts--Configuring DC motor as a switch using Arduino


In this example, we will use our 2N2222 transistor and an Arduino board to interface our motor. Importantly, this circuit can control any DC motors by switching implemented circuits with transistors as switches. Also, you may recognize these types of led flashing drives from your car or home, and their uses are for turning things on/off quickly (and making them blink).


        2n222 pinouts--Configuring DC motor as a switch using ArduinoV    

 (Configuring DC motor as a switch using Arduino)


6. Applications of a 2n2222 NPN Transistor.


  • First, a vital application of this transistor is in high-power application systems.
  • Second, it can perfectly fit in amplification applications.
  • Also, it efficiently works when used in an inverter and other rectifier circuits.
  • Lastly, it is usable in the Darlington transistors.


7.2n222 Pinouts--FAQs


The function of the 2N2222 transistor?


A 2n2222 transistor amplifies low-power to high power or works as a switch in switching applications.


2n222 pinouts--Where is and how to use 2n2222?


A 2n2222 NPN transistor switches loads of higher current into low. Moreover, a 2n2222 transistor can work as a switch or an amplifier. Consequently, when used as a switch, the transistor allows a large current to flow through the collector. And also, it can flow a small current through the base.


What are the significant differences between the 2N2222 and 2n2222A?


The 2n2222A is more expensive with higher voltage. In addition, the 2n2222 is cheaper compared to the 2n2222A because of their old build style.


  7. Summary


2N2222 transistors are one of the most common transistors in the world today. It has a 3-pin configuration. Notably, their uses are rapidly growing in industrial applications, engineering projects, and many more. Meaning that 2n2222 transistors are here to stay.

We hope that this article has answered some of your questions about this transistor. If you liked it, please check out more articles from us. For more information do not hesitate to contact us!