Page 158 - 30105-2003 การวิเคราะห์วงจรอิเล็กทรอนิกส์ความถี่สูง
P. 158

150

               3.



                                                  1
                 ก !ก   (2.17)                    F =
                                          H
                                               π
                                                    C
                                              2 R FH T
                                                      r bb′  b′  C =  C b e ′ +  C b c ′  (1 g R+  m out )
                                                                T
                                                                  Q 1
                                                        r b e ′  C T
                                       E
                                         2 i



                                                            R FH
                                               R
                                                           R
                                                                     r
                                                   R
                                   R FH  =    { CF 2 BB  + r bb′  ( CF 2  +  R BB  )} b e ′
                                                               +
                                         R
                                             R
                                                                           r
                                        { CF  2 BB  +  r bb′  ( R CF  2  +  R BB  )} ( R CF  2  +  R BB  ) b e ′
                                             	+    3.20     ก  + %!   9  R
                                                                        FH
                                                    )

                 ก !ก   (2.18)              A  =  (0.707 A    − 45
                                       V  (F H  )     V (F Mid )
                
      ก  A     =  A
                         V (F Mid )  V  (F R  )
                                                V o
                                                          )
                                                                   −

                                      A V (F H  )  = −  =  (0.707 A V (F R )                 (3.32)
                                                                    45
                                                         E i 1

               "#    
     3.22    ก 	+    3.17   + %!   9  I B  , I C ,V CE , F B W  , A V  (F R  ) , F   %T =  25 C
                                                                  ,
                                                                               H
                                                                 R
                                                                                      A
                                                                 ×
                                                                     ×
                                                V CC B 2      12 6.9 10 3
                                                   R
                 -  ,
    ก !ก   (2.1)         V TH  =   =                   = 2.679 V
                                                                  3
                                                                       ×
                                                              ×
                                              ( R B 1  +  R B 2 )  ( 24 10 +  6.9 10 3 )
                                                                  3
                                                              ×
                                                                       ×
                                                R R   2     24 10 ×  6.9 10 3  5.359 kΩ
                                                  B
                                                   1 B
                 ก !ก   (2.2)                     R  =   =                   =
                                          TH            )
                                                              ×
                                                                  3
                                              ( R B 1  +  R B 2  ( 24 10 +  6.9 10 3 )
                                                                        ×
                                                 V   − V   )         ( 2.679 0.6−  )
                 ก !ก   (2.3)                       I =  ( TH  BE  =                  =  49.833 µA
                                           B                             3
                                                                     ×
                                              R TH  + (β +  ) 1 R E  5.359 10 + (101 360×  )
                                                      F
                 ก !ก   (2.4)                       I = β  I = 100 49.833 10 − 6  = 4.983 mA
                                                        ×
                                                               ×
                                          C    F B
                                                                       }
                                                    I R +
                 ก !ก   (2.5)                    V CE  = V CC  −  { C C  ( β +  ) 1 I R
                                                                   B E
                                                             F
                                                                   ) (
                                                        ×
                                                                                 ×
                                                                         ×
                                                               V CE  = 12 −  ( {  4.983 10 − 3 × 840 +  101 49.833 10 − 6 × 360 )}
                                        V CE  =  6 V
                                                                    ×
                                                                               ×
                                              I C (dc )  I C (dc )  4.983 10 − 3 × 1.60 10 − 19
                 ก !ก   (1.9)                       g =  =   =                       = 193.872 mS
                                          m
                                                                    ×
                                               V T    (k T q )  1.38 10 − 23  (273 25+  )
                                                       B
                                              β        100
                 ก !ก   (1.10)                    r b e ′   =  o  =  = 515.804 Ω
                                                          ×
                                              g m  193.872 10 − 3
                                                                         ก         	
    
    ก  
  ก
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