Page 242 - 30105-2003 การวิเคราะห์วงจรอิเล็กทรอนิกส์ความถี่สูง

234
6.

Ω
Ω

! 6.3 !!# 4
2 ( ( !' ( '( r bb′ = 2 , r b e ′ = 1.5 k ,
Ω
C = 1.5 pF, C ce = 0.5 pF, R out = 1 k ;" !7'

2 700 MHz 6
4 ก ! ;2
T
! # 4' 6.8 ! " C , R , L , L , B , B B
ip ip mi mo W in W out W
r r
"# $ ก !ก (6.9a) R = , X = ;
ip ip
cosθ sinθ
2
( r bb′ + r b e ′ ) + ( C r rω T bb b e ′ ) 2
′
(4' r =
2
1 + ( C r ) 2
ω
T b e ′
( 2 1.5 10 3 ) ( 2 3.14 700 10 × 1.5 10 − 12 × 2 1.5 10 3 ) 2
2
6
×
×
×
+
×
×
+
×
×
r =
1 + ( 2 3.14 700 10 × 1.5 10 − 12 × 1.5 10 3 ) 2
6
2
×
×
×
×
×
2.256 10 + 391.327
×
6
r = = 151.098 Ω
+
1 97.831
2 1.5 10 
6
×
×
 ω C r r   6.28 700 10 × 1.5 10 − 12 × × × 3
×
′
θ = tan − 1  T bb b e ′  = tan − 1  
1
+
×
 r bb′ + r b e ′    2 1.5 10 3  
(
)
θ = tan − 1 0.01317
1
6
×
×
×
θ = tan − 1 ( C r ) = tan − 1 ( 6.28 700 10 × 1.5 10 − 12 × 1.5 10 3 )
×
ω
2 T b e ′
θ = ( tan − 1 9.891 )
2
) (
)
θ = θ − θ = ( tan − 1 0.01317 − tan − 1 9.891 = − 83.472
1
2
r 151.098
R = = = 1.329 kΩ
ip
cosθ cos ( 83.472− )
r 151.098 ( )
X = = = − 152.084 Ω − X = X
ip ip C
−
sinθ sin 83.472 ip
1 1
C = ω X C ip = ( 2 3.14 700 10 × 152.084 ) = 1.495 pF
ip
6
×
×
×
1 1
ก !ก (6.11) L mi = 2 = 2
(2 Fπ R ) C ip 1.495 10 − 12 ( 2 3.14 700 10 6 )
×
×
×
×
L mi = 34.613 nH
1 1
ก !ก (6.13) L mo = 2 = 2
(2 Fπ R ) C ce 0.5 10 − 12 ( 2 3.14 700 10 6 )
×
×
×
×
L = 103.493 nH
mo
3
×
R R 1.329 10 × 75
ip S
=
ก !ก (6.14) R bwi = ) ( 3 = 70.993 Ω
R +
×
( ip R S 1.329 10 + 75 )
ก

ก
ก