Basics of 2N2222 Transistor- Pinout, Specs & Equivalent

Last updated on March 19th, 2024 at 01:49 pm

2N2222 is an NPN – BJT (Bipolar Junction Transistor) which means that in between the two N-doped layers, there is a single P-doped layer embedded with it.

2N2222 is a current-controlled transistor. Thus, a low current at the base terminal can be used to drive a high current between two other terminals.

It is used for switching applications or low power amplifying. It can also be used for pulse width modulation as its response time is fast.

Note: 2N2222A Transistor is the TO-92 plasitic enclosure version of 2N2222 with better absolute maximum ratings; Veb, Vcb, and Vce. Some companies call 2N2222 transistor "2N2222A' now and manufactures 2N2222A only.
Note: PN2222 Transistor is a cheaper version of 2N2222. It also comes in the plastic TO-92 packaging.


The pinout diagram of 2N2222 shows that there are three pins: emitter, base, and collector respectively from left to right(flat side with the leads pointed downward).

2N2222 Pinout(TO-92 Package)
2N2222 Pinout(TO-92 Package)

Note: Give above is the pinout of PN2222/2N2222A Transistor, the TO-92 version of 2N2222. PN2222 is not mentioned in the pin diagram in order to keep things simple.

2N2222 Pinout(TO-18 Package)
Original 2N2222 Pinout(TO-18 Package)
1EmitterThis pin act as an inlet as the current enters the transistor from here. The collector is denoted by ‘C’.
2BaseThis pin controls the transistor biasing. The base is denoted by ‘B’.
This pin act as an outlet and the current comes out of the transistor from here. The emitter is denoted by ‘ E’.
Pin description

2N2222 VS 2N2222A: What’s the difference?

Both are similar types of transistors but the 2N2222A has higher Maximum absolute ratings than 2N2222. The Collector to Base, Emitter to Base, and Collector to Emitter voltage ratings of 2N2222 and 2N2222A are 60V, 30V, 5V and 75V, 40V, 6V respectively.

Also, the 2N2222 comes in metal packaging whereas the 2N2222A is available in TO-92 plastic enclosure only.

2N2222A is a better option considering its higher ratings, low cost, and TO-92 packaging.


The technical specifications of 2N2222 in TO-18 metal packaging and 2N2222A transistor in TO-92 packaging are given below:

Power Dissipation(TC = 25°C)1.51.2W
DC Current Gain (hFE)30-30030-300
Operating Temperature Range-55 to 150°C-65 to 200°C
Continuous Collector Current (IC)0.6 A0.8 mA
Collector-Base Voltage(VCB)7560V
Emitter-Base Voltage(VEB)65V
Collector-Emitter Voltage(VCE)4030V
Input Capacitance(CI)25pF30pF
Output Capacitance(CO)8pF8pF
Transistor typeNPNNPN
Mounting TypeThrough-holeThrough-hole
Transition frequency(Ft)250MHz
This table shows the technical specifications of the 2N2222 Transistor

The exact specifications depend on the manufacturer, case type, and variation. Therefore, it is important to refer to the datasheet for the exact part number and manufacturer.

Which transistors are equivalent to 2N2222?

Given below is the list of transistors that are equivalent to 2N2222 and can be used as a replacement.

Can a BC547 be replaced with 2N2222?

Yes, we can replace BC547 with 2N2222. BC547 transistor is considered the best equivalent of 2N2222 & can work well in your projects. Although using an equivalent transistor requires a detailed comparison, the BC547 is still a good alternative to 2N2222.

Are there any differences between 2N2222 and BC547 Transistor?

Between BC547 & 2N2222, there are minor changes in output and input capacitance. The input and output capacitance of 2N222 is slightly higher than BC547. This affects the circuit while operating at a higher frequency.

Other differences between both transistors are given below:

Collector to Base voltage60V50V
Collector to Emitter voltage30V45V
Emitter to Base voltage5V6V
Maximum collector current800mA100mA
DC Gain75-300HFe110-800HFe
Thermal resistance146k/w83.3°C/w
Transition frequency250MHz300MHz
Noise figure4db10db
This table shows the differences between BC547 and 2N2222

Uses and applications

2N2222 is used in a variety of electronic projects due to its excellent features like a larger collector current 600mA. This feature makes it ideal for electronics projects like controlling high-power LEDs, relays, high-power transistors, and ICs.

The applications of this transistor are:

  • Motor driver circuits
  • Switching circuits
  • Amplifier circuits
  • Sensors circuits
  • Audio preamplifier
  • Low power application
  • Inverter circuits
  • RF circuits
  • Darlington Pair
  • Embedded and automation projects

Datasheet of 2N2222 transistor

Given below is the datasheet in the TO-18 Metal can package:

Download 2N2222 TO-18 package datasheet

Given below is the datasheet in the TO-92 package:

Download P2N2222A TO-92 package datasheet

This transistor has several variants collectively called as “2N2222 type” and they are identical to the original 2N2222 transistor in terms of operation and functionality.

Among these transistors, P2N222A is the main transistor, which is available in the TO-92 package made of either plastic or epoxy. Due to its number of advantages and low cost, the TO-92 package of P2N222A has become the most used and cost-effective transistor in electronics.

Where to buy 2N2222(TO-18)?

You can easily find these transistors in your local electronics store. For online purchases, we recommend this best deal on Amazon:


Given below are the dimensions of its TO-18 package. All the dimensions are in mm.

2N2222 Transistor dimensions(TO-18 Package)
2N2222 Transistor dimensions(TO-18 Package)
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Ankit Negi

I am an electrical engineer by profession who loves to tinker with electronic devices and gadgets and have been doing so for over six years now. During this period, I have made many projects and helped thousands of students through my blog and YouTube videos. I am active on Linkedin.

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