Page 115 - 30105-2003 การวิเคราะห์วงจรอิเล็กทรอนิกส์ความถี่สูง
P. 115

107
                     2.




                             V R          V R             V
                                                  -
                          I =  G  2   . -   I =  G 1   .    I =  DD  (
-     ก R     R  	  
)ก  ก
                                                                            1
                                                                                   G
                                                                                    2
                                                                           G
                             R G 2         R G 1       (R G 1  +  R G 2  )
                                              V R G 1  = V DD  − V R G 2
                                                                     V  − V
                                               R  =  DD    R G 2
                                                G 1
                                                        I
                                 V R
                     *  ( - ก  I =  G 2
                                 R G 2
                                                                 V
                                                    V DD  − V R  ( DD  − V R  ) R G 2
                                                                     R  =  G 2  =  G 2
                                                G 1
                                                        I            V R
                                                                        G 2
                                                     V   − V   ) R
                                                    ( DD   R G 2  G 2                                                (2.66)
                        
 $
                                     R  =
                                                G 1
                                                         V R G  2

                      ,    
     2.31    ก  ,%   2.34    ก  ,      	  R  , R R     R
                                                                     ,
                                                                D   S  G 1     G 2
                                                                    −
                       -  .
    ก  ก   (2.61)        V R S  =  0.586 V P  = 0.586 4 = 2.344 V
                                                                   =
                                                               ×
                       ก  ก   (2.62)                  V DS  =  0.5V DD  = 0.5 20 10 V
                       ก  ก   (2.63)                  V  =  V  −  V  + V  ) =  20 − (10 2.344+  ) 7.656 V=
                                               R D   DD  ( DS    R S
                              "
                     ก  .
  .                                 I =  0.5I  =  0.5 8 10 − 3  = 4 mA
                                                               ×
                                                                  ×
                                                D      DSS
                                                    V R    7.656
                       ก  ก   (2.64)                    R =  D  =  = 1.914 kΩ
                                                D             − 3
                                                           ×
                                                    I D   4 10
                                                    V R   2.344
                       ก  ก   (2.65)                    R =  S  =  = 586 Ω
                                                S
                                                           ×
                                                    I D  4 10 − 3
                     ก  .
  ."                              R G 2  = 47 kΩ
                       ก  ก   (2.65a)               V  = V = 0.293V + 0.586 V  ((H3  (/  '	  ( +
)
                                              R G 2  G        P         P
                                                                   V  =  {0.293 ( )} ( 0.586 4− 4  +  −  ) 1.172 V=
                                               R G 2

                                                     V   − V   ) R             )   ×  3
                                                    ( DD   R G 2  G 2  (20 1.172 47 10−
                       ก  ก   (2.66)                   R G 1  =     =                   = 755.047 kΩ
                                                         V R                1.172
                                                           G 2
                           R = == =  1.914 k , R = =Ω Ω  S  = =  586  , R G 2  = = = =  47 k , R G 1  = = = = 755.047 k ;
                                                                              Ω
                                                                              Ω Ω Ω
                                                 Ω Ω Ω
                                                 Ω
                                                             Ω
                                                             Ω Ω Ω
                                      Ω Ω
                            D
                                    2.2.5.3  ก
 )+      
  
   
  
  $  )D   
 
 
E
                                            '"     %   A-1  
;  <
 ก ก.
                                           R =  1.914 kΩ (,5
 	     4 
  R = 2 kΩ
                                                                         D
                                            D
                                                                                  ก         	
    
    ก  
  ก
   110   111   112   113   114   115   116   117   118   119   120