The Engineering Projects

Introduction to 2N2222

Hello everyone! I hope you will be absolutely fine and having fun. Today, I am going to give you an Introduction to 2N2222. It is the most commonly used Negative-Positive-Negative (NPN) Bipolar Junction Transistor (BJT) available in the market now a days. 2N2222 can be used for different purposes e.g. switching and amplification of analog signals. I hope you have enjoyed the previous post on Introduction to ULN2003. The major functional area of 2N2222 is enclosed in TO-18 package. Due to the low cost and small size it is the most commonly used transistor. One of its key features is its ability to handle the high values of currents as compared to the other similar small transistors. Normally it is capable of switching a load current of 800mA which is really high rating as compared to other similar transistors. It is either made up of silicon or germanium material and doped with either positively or negatively charged material. Its applications may include amplification of analog signals as well as switching applications. While performing amplification applications, it receives an analog signal via collectors and another signal is applied at its base. Analog signal could be the voice signal having the analog frequency of almost 4kHz (human voice).

Introduction to 2N2222

2N2222 is the most common NPN bipolar junction transistor available in the market. It can be used for amplification of analog signals as well as switching applications. The major functional area of 2N-2222 is enclosed in TO-18 package. It is most common in the market due to the cost efficiency and the smaller size.

• It is shown in the figure shown below.

1. 2N2222 Pinout

• 2N 2222 has 3 pins in total, which are:
  1. Pin # 1: Emitter.
  2. Pin # 2: Base.
  3. Pin # 3: Collector.
• 2N2222 Pinout is shown in the figure below:

2. 2N2222 Pin Description

• The functions associated with each pin of 2N2222 along with the pin names are shown in the table given below.

• That was the description of the pins of the transistor.
• Pin configuration is shown in the figure below.

 

3. 2N2222 Voltage/Current Ratings

• The current, power and voltage ratings for 2N 2222 transistor are shown in the table given below.

• From the above table you can see the voltage across collector base junction is almost double as compared to the voltage across collector emitter junction.
• emitter base voltage is 12 times lesser than the voltage across the collector emitter junction.
• It can drive high amount of current loads as compared to the other similar transistors i.e. 800mA.
• This IC should be operated between the temperature ranging from -65 to 200 degree celcius.
• That was the brief description of the power, current and voltage ratings of the IC 2N2222.

4. 2N2222 Characteristics

The key characteristics associated with 2N2222 are given below.

• The total power of this component should not exceed by 500mW.
• The maximum capacity of handling frequency is 250MHz.
• For the collector current of 10mA and for 10 volts the DC current is around 75.
• Maximum tolerance of 2N2222 is 60V across its base and collector.
• Some of the other characteristics are shown in the table given below.

• That was the brief description about the key characteristics of the transistor 2N2222.

5. 2N2222 Simulation in Proteus

• I have also made a two different simple simulation in Proteus ISIS using the transistor 2N2222.
• The Proteus ISIS simulation for controlling an LED using 2N2222 is shown in the figure given below.

• If you change the state of the logic state from 0 to 1, current will be supplied to the collector and hence an LED attached to its emitter will be turned on.
• The running form of the above simulation is shown in the figure below.

• I have made another simulation in Proteus ISIS to control a simple DC motor using Arduino UNO.
• The simulation of the task is shown in the figure below.

• Source code for the above simulation is given below.

int MotorInput = 2;
int MotorOutput = 7;

void setup()
{
  pinMode(MotorInput, INPUT_PULLUP);
  pinMode(MotorOutput , OUTPUT);
}

void loop()
{
  if (digitalRead(MotorInput) == HIGH)
  {
    digitalWrite(MotorOutput, HIGH);
  }
  if (digitalRead(MotorInput) == LOW)
  {
    digitalWrite(MotorOutput, LOW);
  }

}

• You have to just copy and paste the entire code into the Arduino software.
• Obtain its .hex file and insert it into the Arduino of the Proteus ISIS.
• The running form of the above simulation is shown in the figure below:

• You can download the complete Arduino source code and simulation in one package, here by clicking on the button shown below.

Proteus Simulation & Arduino Code

So that is all from the tutorial Introduction to 2N2222. I hope you enjoyed this tutorial. If you face any sort of problem regarding any thing, you can ask me anytime in comments without even feeling any kind of hesitation. I will try my level to entertain you and to solve your issues in a better way, if possible. Our entire team is 24/7 here to entertain you and to solve your issues in a way or the other. I will explore different IC's in my later tutorials and will surely share all them with all of as you as well. So, till then, Take Care :)