BC547: Datasheet, Pinout, Working, Applications and Simulation

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Its maximum current gain is around 800. So, let's have a detailed overview of BC 547.

Introduction to BC547

• BC547 is a 3-Terminal NPN Bipolar Junction Transistor(BJT), mostly used for switching purposes and current amplification.
• BC547 Pins(Terminals) from left to right are called:
  • Collector.
  • Base.
  • Emitter.
• Depending on the voltage applied at Base Terminal, BC547 can operate in two states, named:
  • Forward Biased.
  • Reverse Biased.

BC547 as Reverse Biased

• If Base Terminal is connected to the Ground(0V), Collector and Emitter will act as an open switch and the transistor is said to be acting as Reverse Biased.
• In a Reverse Biased State, no current will flow through the transistor.

BC547 as Forward Biased

• If a HIGH signal(normally 5V) is provided at the Base Terminal, Collector and Emitter will start acting as a closed switch and the transistor is said to be acting as Forward Biased.
• In Forward Biased State, the current will start flowing from Collector to Emitter.
• The maximum Collector current limit of BC547 is 110mA, so the load must be lower than that.

• Now let's have a look at the datasheet of BC547:

BC547 Datasheet

• If you want to get in-depth knowledge about any electronic component, then you should read its datasheet.
• You can download BC547 Datasheet by clicking the below button:

• Now, let's have a look at the pinout of BC547:

BC547 Pinout

• BC547 Pinout consists of 3 pins in total, named: Collector(C), Base(B) and Emitter(E).
• All of these three pins along with their symbols are shown in the below table:

BC547 Pins Configuration

• The properly labeled pin configuration diagram of BC 547 along with its animation is shown in the figure given below.

• In the last section, we will design a Proteus Simulation of BC547, which will give you a better understanding of How to use these pins of BC547.

BC547 Transistor Working

• As we know BC547 is an NPN transistor, so in its design, a P-region(Base) is sandwiched between two N-type regions.
• At the border of the P and N, a depletion region is created, which blocks the flow of charge carriers from one region to another.
• When the input voltage is applied at its Base terminal, some amount of current starts to flow from the base to the emitter and controls the current at the collector.
• The voltage between the base and the emitter (VBE), is negative at the emitter and positive at the base terminal for its NPN construction.
• The polarity of voltages applied for each junction is shown in the figure below:

BC547 Ratings

• The current, power and voltage ratings of BC547 along with their values and System International (SI) units are provided in the table shown below.

• Moreover, the storage temperature, as well as operating temperature for the transistor BC 547, is also given in the table shown above.

BC547 Thermal Characteristics

• The thermal characteristics associated with BC 547 are provided along with typical values, in the table shown below.

BC547 Applications

• There are a lot of applications associated with BC547, a few of the major applications are given below.
  • BC547 can be used for switching purposes.
  • We can also use it for amplification purposes.

BC547 Proteus Simulation

• I have made a simple Proteus ISIS simulation using BC 547 for the control of the DC motor.
• The screenshot of the simulation is shown in the figure below.

• The running form of the simulation is shown in the figure below.

• By pressing the button encircled in the figure above, you will be able to observe the working of the DC motor.
• I have made another simulation for DC motor control using Arduino UNO and BC 547.
• The simulation's screenshot is shown in the figure below.

• The 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);
    }
  
}

• The running form of the simulation is shown in the figure below.

• First of all, you need to change the logic state from 0 to 1, after uploading the hex file, the motor will automatically start to rotate.