Page 77 - 30105-2003 การวิเคราะห์วงจรอิเล็กทรอนิกส์ความถี่สูง

69
2.

R BB
,% 2.11
(β o +1 )



(r bb′ + r b e ′ )  R g R 
R = +  BB 
EE
( β + ) 1   ( β + 1 ) (β + ) 1  
o
o
o
r
= ( bb′ + r b e ′ ) + R R
g BB
R
EE
( β + ) 1 (β + 1 )( R + R BB )
o
g
o
R R
E EE
R FLCE = ( R R EE ) =
E
( R + R EE )
E
r bb′ b′
r b e ′
E
g
( bb′ + r b e ′ )
r
β + ) 1

( o ( bb′ + r b e ′ )   R g R BB 
r
R = +  
EE β + β + β +
( o ) 1   ( o 1 ) ( o ) 1  
R g R BB ( bb′ + r )   R R 

r
β + ) 1 β + ) 1 R EE = b e ′ +  g BB 
( o ( o β + β + 1 R +

( o ) 1   ( o )( g R BB )
R R
R = R R ) = E EE
FLCE ( E EE R + )
( E R EE
R R
EE FLCE

,% 2.11 , R
FLCE

,
2.6 ก ,% 2.1 , F ( L C E )
1
- .
ก ก (2.14) F ( L C ) =
π
E
2 R FLCE C E
R R
E EE
* % R FLCE = ( R R EE ) =
E
( R + R EE )
E
+
×


(2 588.64 )  75 7,500 
=
+
R EE = ) +  )(  = 5.847 0.735 6.582 Ω
(100 1+   (100 1 75 7,500+ + )  
×
R R 470 6.582
E EE
R FLCE = = = 6.491 Ω
( R + R EE ) (470 6.582 )
+
E
1 1
F = = = 2.453 kHz
( L C E ) − 6
π
×
×
×
×
2 R FLCE C E 2 3.14 6.491 10 10
F ( L C E ) = == = 2.453 kHz
ก

ก
ก