(Definitions at bottom)

DEVICE -------> 2N2222    2N2222A    2N3904    2N3906    2N4401    2N4403
TYPE/USAGE      NPN GPA   NPN GPA    NPN LNA   PNP LNA   NPN GPA   PNP GPA
          CASE   TO-92     TO-39      TO-92     TO-92     TO-92     TO-92
MAXIMUM RATINGS
          Vce V     30        40         40        40        40        40
          Veb V      5         6          6         5         6         5
         Ic  mA    800       800        200       200       600       600
          Pd  W    0.4       0.8        0.6       0.6       0.6       0.6

SMALL SIGNAL 
CHARACTERISTICS
     Vbe(sat) V  0.6-1.3   0.6-1.2    0.7-0.9   0.7-0.9   0.7-1.0   0.7-1.0
     hfe (gain)   50-300    50-300    100-400   100-400    40-500    60-500
        Ft  MHz    250       300        300       250       250       200
      Noise Fig.   4dB       4dB        5dB       4dB       --        --
      hie (Zin)   2K-8K     2K-8K      1K-10K    2K-12K    1K-15K    1K-15K
         Cin pF     30        25          4        10        30        30
        Cout pF      8         8          8         5         6         9
          Tr nS     25        25         50        50        20        20
          Tf nS     60        60         90        90        30        30

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DEVICE -------> MPS918    MPS2222    MPS5179    2N5109
                          (2N2222)   (2N5179)    
 TYPE/USAGE     NPN HFA   NPN GPA    NPN HFA    NPN HFA
       CASE      TO-92     TO-92      TO-92      TO-39
MAXIMUM RATINGS
      Vce V         15        40         12         20
      Veb V          3         6          2.5        3
     Ic  mA         50       800         50        400
      Pd  W          0.4       0.8        0.2        2.5

SMALL SIGNAL 
CHARACTERISTICS
 Vbe(sat) V     1.0 max   0.6-1.2    0.7-1.0    0.7-1.1
 hfe (gain)      20-250    50-300     25-300     40-120
     Ft MHz         900       300       2000       1200
  Noise Fig.        6dB       4dB        5dB        3dB
  hie (Zin)          na    2K-8K          na        50K
     Cin pF           2        25          2          7
    Cout pF           3         8          3          3
Gve (V. Gain)      11dB
Gpe (Pwr Gain)     15dB      15dB
  Tr/Ton nS          na        25         na         na
Tf/Toff nS           na        60         na         na

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CASE: TO-92=encapsulated plastic EBC TO-39=metal can EBC 
USAGE: GPA=gen. purpose amp. LNA=low noise amp HFA=high freq. amp. 
Vce= Max. collector-emitter volt.   
Veb= Max. emitter-base volt.
Ic= Max. collector current  
Pd= Max. power dissipation
Vbe(sat)=base-emitter saturation voltage, min-max range 
hfe= gain (frequency dependent) 
Ft= max. freq. (where gain=1)
hie= approx. input impedance    
Cin/Cout= in/out capacitance
Tr/Ton= turn-on time 
Tf/Toff= turn-off time [for digital switching times] 

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| *** TO-92        |   B* TO-39        |
| *** Plastic      | *E C* metal can   |
| ||| (looking at  |  // (bottom view) |
| EBC flat side)   | Tab               |
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REF: Motorola Small Signal Transistors Device Data Book, 1991 ed. 

(pharden@nrao.edu)