Page 183 - 30105-2003 การวิเคราะห์วงจรอิเล็กทรอนิกส์ความถี่สูง

175
4.

1

ก 4.8 D ก (. .0 D 4
ก (.
2
1
*
π
π
R i ( -2 ) !
0 (
# - ก -ก %$% 5( & R , ( -2 )
π
π
BB
R R 2
E
R = ( R R ) =
EP 1 E 2
( R + R 2 )
E
! ก R

1
ก
5( & 4%
! 0 # ก - R
0

2
E
% & R = r + r + (β + ) 1 R (4.14)
π
π
i ( -2 ) bb′ b e ′ F EP 1
R R ( -2 )
π
π
BB i
% & R in π π = (4.15)
( -2 )
R + R
π
π
BB i ( -2 )

*& 4.12 (
R i ( -2 ) .5( R in ( -2 )
π
π
π
π
+ , ก
ก (4.14) R i ( -2 ) = r bb′ + r b e ′ + (β + ) 1 R
π
π
EP
1
F
Ω
Ω
$% r b e ′ = 461.981 , R = 560 , E = 25 mV peak ;
E
i
×
×
R R 2 560 2 10 6 559.843 Ω
E
R EP 1 = = =
( R + R 2 ) ( 560 2 10 6 )
+
×
E
R i ( -2 ) = (r bb′ + r b e ′ ) ( β+ F + ) 1 R EP 1
π
π
R i π π = ( 2 461.981+ ) + (101 559.843× ) 57.008 k= Ω
( -2 )
R R ( -2 )
π
π
BB i
ก
ก (4.15) R in π π =
( -2 )
( R BB + R i π π )
( -2 )
Ω
Ω
$% R BB = 8.432 k , R i ( -2 ) = 57.008 k ;
π
π
3
×
×
8.432 10 × 57.008 10 3
R = = 7.345 kΩ
( 8.432 10 + 57.008 10 3 )
π
π
in ( -2 )
×
3
×
Ω
Ω
Ω Ω Ω
Ω Ω Ω
* R i π ππ π = = = = 57.023 k , R in π ππ π = = = = 7.345 k ;
π
π
π
π
π
π
π
π
( -2 )
( -2 )
I ! ก (. 4==D 4
5; D , ( -2 )# D % # R
π
π
d
1
1
1

1
! 0 #
5( & 4%
R C
I d 1 = g V
m b e ′
R +
d
C r + R L
1
E r
i b e ′
! ก V b e ′ =
R
π
π
i ( -2 )
E g r R (4.16)
′
i m b e C
% & I d 1 =
R +
R i ( -2 ) ( C r + R L )
π
π
d
1
ก

ก
ก