Page 159 - 30105-2003 การวิเคราะห์วงจรอิเล็กทรอนิกส์ความถี่สูง
P. 159

151

                     3.


                                                                                   ×
                                                                      R R       840 75   68.852 Ω
                                                                       C L
                       ก !ก   (2.9)                    Z  =  R  =  ( R    R  ) =  =    =
                                               out   out    C   L    R +    )      +
                                                                    ( C   R L   840 75
                                                                r
                                                           R BB  ( bb′  +  r b e ′  )
                       ก !ก   (3.30)                 Z  =  R  +
                                               incf  CF  2              )
                                                          ( R BB  +  r bb′  +  r b e ′
                                                                       3
                                                                    ×
                                                                             ×
                                                      R R  2      24 10 × 6.9 10 3   5.359 kΩ
                                                        1 B
                                                       B
                                                                    R  =  =        =
                                               BB            )
                                                    ( R B 1  +  R B 2  ( 24 10 +  6.9 10 3 )
                                                                       3
                                                                    ×
                                                                             ×
                                                                         )
                                                     V o             (0.5 g Z   r R
                                                                                 ′
                                                                           m out b e BB
                       ก !ก   (3.31)              A  = −  = −
                                             V (F R )  E i 1  R CF 2  ( R BB  +  r bb′  +  r b e ′  ) R+  BB  ( bb′  +  r b e ′  )
                                                                                      r
                     ,          C b c ′  =  C ob  = 0.5 pF
                                                       ×
                                    g m         193.872 10 − 3       − 12  3.910 pF
                                                                  ×
                                    C b e ′  =  −  C ob  =    −  0.5 10  =
                                    π
                                                      ×
                                                         ×
                                                ×
                                   2 F T       2 3.14 7 10  9
                                                                                         ×
                                                                       ×
                                    C =  C b e ′  +  C b c ′  (1 g R+  m out  ) 3.910 10=  ×  − 12  +  0.5 10 − 12 { 1+ ( 193.872 10 − 3 × 68.852 )}
                              T
                             C = 11.084 pF
                              T
                                    R BB  = 5.359 kΩ
                                                                         )
                                                      V o            (0.5 g Z   r R
                                                                                 ′
                                                                           m out b e BB
                                            A V (F R )  = −  = −                              )
                                                      E
                                                       i 1  R CF  2  ( R BB  +  r bb′  +  r b e ′  ) R+  BB  (r bb′  +  r b e ′
                                                                                                ×
                                                                    ×
                                                           ×
                                                                                         ×
                                                                                 ×
                                                         0.5 193.872 10 − 3 ×  68.852 515.804 5.359 10 3
                                                                A  = −
                                                        (
                                             V (F R )            3                       3
                                                                                                     )
                                                                                             +
                                                     75 5.359 10 + +          )  5.359 10  (2 515.804
                                                                                      ×
                                                                    2 515.804 +
                                                              ×
                                            A     = − 5.737
                                             V (F R )
                                                        1
                       ก !ก   (3.32)                    F =
                                                H
                                                     π
                                                    2 R   C
                                                        FH T
                                          r b e ′  { CF 2 BB  +  r bb′  ( CF 2  +  R BB )}
                                                            R
                                                   R
                                              R
                     ,           R  =
                              FH            +          +                 +    )
                                         R
                                                                    R
                                    R
                                                  R
                                   { CF 2 BB  r bb′  ( CF 2  R BB )} r+  b e ′  ( CF 2  R BB
                                                    ( {          3 ) (              3 )}
                                                                                ×
                                                                          +
                                                       ×
                                                              ×
                                            515.804  75 5.359 10    +  2 75 5.359 10
                              R FH  =  ( {        3                 3 )}                     3
                                                                                (
                                        ×
                                                                                   +
                                                                                          ×
                                              ×
                                                    +
                                                     2 75 5.359 10
                                      75 5.359 10  ) (    +      ×     +  515.804 75 5.359 10  )
                                                 ×
                                          212.920 10 6
                              R FH  =                        = 66.231 Ω
                                    ( 412.793 10 +  2.802 10 6 )
                                               3
                                            ×
                                                       ×
                                   C = 11.084 pF
                              T
                                                                 1
                                                                      F =       = 216.911 MHz
                                                H
                                                                         ×
                                                           ×
                                                     ×
                                                                  ×
                                                    2 3.14 66.231 11.084 10  − 12
                                                                 ±
                                                                          −
                                                                       F R  = 5.5 MHz, B W = 60 kHz ( 3 dB);
                     "     I = == =  49.833 µA, I = == =  4.983 mA,V CE  = = = =  6 V, F R  = 5.5 MHz, B W  = 60 kHz ,
                                                                                   ± ± ±
                                                                                   ±
                            B
                                          C
                                             =
                                 = − −− −
                               A  == =  5.737, F == = 216.911 MHz;
                            V (F R )       H
                                                                               ก         	
    
    ก  
  ก
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