2n3904 pinout, 2n22 pinout, 2n4401 pinout, BC547 pinout and etc… I need these transistors last days. There is an easy way for knowing electronic componets’s pinout. Also there is an easy way for knowing transistor’s pinout. We will share some tips on this topic. Before, Let’s give a few brief information about transistors.
What is transistor?
Invented by Willian Shockley, John Bardeen and Walter Brattain at Bell Laboratories in 1947, the transistor is considered the most important invention of the 21st century. These men shared Nobel Prize for this invention.

Transistor has 2 using purpose:
- As an amplificator
- As an switching device
Classification of Transistors
Some letters and numbers used for classifiction of transistors. These give us a lot of informations of that transistor. There are 3 main classifification:
- USA Standard: 2N..
2: Type of component
N: Silicon
- Europe Standard: AC…, BC….
AC.. : Low power low frequency germanium transistor (AC121, AC187 etc.)
BC…: Low power low frequency silicon transitor (BC547, BC237 etc..)
- Japan Standard: 2S…Â
2: Type of component
S: Silicon
Transistor Pinout
Electronic components have a few packet shape. Also transistors have some packet shape. Transistor’s pinout may vary according to package shape. I have added the most common ones using the following packages:
Most used transistor packages:
TO3, TO66 Package

1- Emitter 2- Base  3- Collector
That transistors have TO3, TO66 package:
2n3055, 2N6545, 2N6547, 2N6609, 2N3054
TO5 Package

1- Emitter 2- Base  3- Collector
That transistors have TO5 package:
2N1711, 2N1893, 2N2219, 2N2905
TO18 Package

1- Emitter  2- Base  3- Collector
That transistors have TO18 package:
2N2222, 2N2222A, 2N2223, 2N2907, 2N2369, 2N3417, BC478,
TO92 Package

1- Emitter  2- Collector  3- Base
That transistors have TO92 package:
2N2926, 2N3702, 2N3704, 2N2705, 2N3706, BC548,
Eline Package

That transistors have Eline package:
Zetex 2N6715, 2N6727, BC380, BC337,
P1, P3 Package

1- Base  2- Collector  3- Emitter
That transistors have P1 package:
2SB718, BD540, BD711, BDX54
Conclusion
There are a lot of different component package. I cant add all of them in this post. I tried to share most used transistor packet shapes.