
Pin3 (Emitter): The emitter pin is the third pin of the transistor & it is used to drain out the complete current of the transistor.ĢN2907(PNP), 2N3904(PNP), 2N3906 (PNP), BC637, S9014, BC148, 2N4403, MPS2222, PN2222, KN2222, KTN2222.The main function of this pin is to control the current from emitter to base. Pin2 (Base): The base pin is a control pin & it is a second pin of the transistor.The main function of this pin is to provide transistor current toward the o/p load. Pin1 (Collector): This is the first pin of the transistor & it is an o/p pin.

This transistor includes three pins & its each pin functionality is discussed below. The pin configuration of the 2N2222A transistor is shown below.

To bias a transistor we have to supply current to base pin, this current (IB) should be limited to 5mA. The maximum amount of current that could flow through the Collector pin is 800mA, hence we cannot connect loads that consume more than 800mA using this transistor. 2N2222A has a gain value of 110 to 800, this value determines the amplification capacity of the transistor. 2N2222A is a NPN transistor hence the collector and emitter will be left open (Reverse biased) when the base pin is held at ground and will be closed (Forward biased) when a signal is provided to base pin.
