NPN; Configuration: SINGLE; Surface Mount: NO; Nominal Transition Frequency (fT): 300 MHz; Maximum Power Dissipation (Abs): .5 W; Maximum Collector Current (IC): .8 A;
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).
BSS138-TP by Micro Commercial Components is a N-channel small signal FET with a min DS breakdown voltage of 50V and max drain current of 0.22A. It is commonly used in applications requiring enhancement mode operation, such as power management and switching circuits.