Buy Aruino   Buy Arduino Uno on AliExpress

How to Identify Pins of a Transistor

Transistor is a semiconductor device that is used to amplify or regulate the path of the electrical signals.

Transistor has a wide variety of applications in various fields. Transistor has basically three pins that are:

  • collector,
  • base,
  • emitter.

If you are using a transistor in your project as an amplifier or switch, you need to know all the three pins of the transistor before start working with it. I will be using a multi-meter to test the pins of the Transistor.

Hardware Required:

  • Transistor;
  • Multi-meter.

To identify these three pins, first, you can identify the BASE which is very easy to identify. Base is generally the middle pin of any transistor. The next step is to identify the other two pins of the transistor:

  1. Take Multimeter
  2. Set the Pointer to HREF
  3. Insert the Transistor into NPN or PNP block
  4. Insert its three legs into ECB or BCE.

If you get any reading then you have correctly identified the transistor. If not, try to insert the transistor into the other configuration of BCE.

If you still didn’t get reading try to insert it into the ECB of PNP (if you tried on NPN first).

Now you will surely get the reading if your transistor is OK!

These are the correct pins of the transistor . When you get reading you just stop.

Note. You can also check whether your transistor is NPN or PNP by searching for its datasheet on Google.

You can check out my other post if you don’t have a multimeter and stuck at finding pins of transistor.