- #1
Clear Mind
- 38
- 3
Suppose to have a BJT Common Emitter amplifier like the one below:
Now, if we send a signal ##V_{in}## with a frequency belonging to the midband frequency interval, we can consider ##C_1, C_2,## and ##C_E## as short circuit. Questions are:
1) What is the effect of ##C_E## (excluding its role on the frequency respond of the amp)?
2) It is right to say that the gain of this amplifier with ##C_E## is:
##A_v=-g_mR_C##
and the gain without ##C_E## is:
##A_v=\frac{-g_mR_C}{1+g_mR_E}##
3) Does the presence of ##C_E## change the values of ##R_{in}## and ##R_{out}##?
Now, if we send a signal ##V_{in}## with a frequency belonging to the midband frequency interval, we can consider ##C_1, C_2,## and ##C_E## as short circuit. Questions are:
1) What is the effect of ##C_E## (excluding its role on the frequency respond of the amp)?
2) It is right to say that the gain of this amplifier with ##C_E## is:
##A_v=-g_mR_C##
and the gain without ##C_E## is:
##A_v=\frac{-g_mR_C}{1+g_mR_E}##
3) Does the presence of ##C_E## change the values of ##R_{in}## and ##R_{out}##?