Electronic Circuit Analysis

Multistage A'mpiifzers
63
!c = 1
e 21t(Rs +RL).C
When Xc = 0.1 (Rs + R L ),
YOU!
Yin
RL
= ~(RS+RL)2+[0.1 (Rs+Rd]2
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V. = 0.995 Amid'
In
Xc is made = 0.1 (Rs + R L ), at the lowest frequency. ife lower)
.. At the frequency, A = 0.995 Amid' So it is called as Stiff Coupling.
R R I
- = -- = 21tjRC = -
Xc 1 Ie
21t Ie
1
fc = 21tRC
Decibel voltage gain A • ~ 20 log ~I+(:')'
When
Ie = cutoff frequency.
I
Ie = 0.1,
1
Al = 20 log '/== == Odb
,,1 +(0.1)2