2N2222A by Texas Instruments is a small signal NPN bipolar junction transistor (BJT) with a max collector-emitter voltage of 40V and a max collector current of 0.8A. It is commonly used for switching applications due to its fast turn on/off times (35ns/285ns) and high transition frequency (300MHz).
FIXED POSITIVE SINGLE OUTPUT STANDARD REGULATOR; No. of Terminals: 3; Terminal Form: THROUGH-HOLE; Maximum Voltage Tolerance: 5 %; Operating Temperature (TJ-Max): 125 Cel; Maximum Output Voltage-1: 5.25 V;
NPN; Configuration: 8 BANKS, DARLINGTON WITH BUILT-IN DIODE AND RESISTOR; Surface Mount: NO; Maximum Collector Current (IC): .5 A; No. of Elements: 8; Minimum DC Current Gain (hFE): 1000;