Peak gain and IP3 of a common-emitter amplifier

AI Thread Summary
The discussion focuses on calculating the peak gain of a common-emitter amplifier. The user initially calculated the gain using the small signal equivalent, questioning the correctness of their approach. Suggestions include consulting basic electronics textbooks for deeper understanding and examples. The conversation also touches on the concept of resonance and its impact on gain calculations, leading to a derived peak gain formula. Ultimately, the user confirms their calculations yield a peak gain of approximately -38.4, or 31.7 dB, indicating a successful resolution of the problem.
DavidEE
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1. Homework Statement
Bildschirmfoto 2015-07-31 um 13.49.12.png

Homework Equations


Hi all.
Lets start with subquestion a).
How do i calculate the PEAK gain?

The Attempt at a Solution


I drew the small signal equivalent and calculated the gain: Av=vo/vi=-gm(ro//R=1kΩ//L//C)
Is that correct? How do i now calculate the peak gain?

Thank you for you help!
 

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DavidEE said:
1. Homework Statement

Homework Equations


Hi all.
Lets start with subquestion a).
How do i calculate the PEAK gain?

The Attempt at a Solution


I drew the small signal equivalent and calculated the gain: Av=vo/vi=-gm(ro//R=1kΩ//L//C)
Is that correct? How do i now calculate the peak gain?

Thank you for you help!
It seems like the best bet would be to look in a basic electronics book. Like for example your course book. You kinda like read the thing, follow through some of the worked examples. Sometimes you get stuck and you have to reread a section a few times or check something on the internet. You are wasting your own time if you really believe you can get through a technical course without reading anything. It would be better to enter the workforce straight away if you can't/won't do the basics. Flip the burgers or read the books. 18+ you're an adult. Mom and pop can't buy you a great job.
 
Wow, that was helpful, thanks!
 
David - do you really mean R||L||C ? Which dimension do you expect as a result?
Have you heard already about the term "resonance"?
 
I mean R||sL||1/sC.
r0 can be neglected.
That would result in jwRL/(R-w^2RCL+jwL).
The peak gain would be at w=1/sqrt(LC)? (Thanks LvW)
After some calculations i get Av=-gmR=-(Ic/Vt)R= -38.4, IAvI=31.7dB
 
Yes - the result looks OK (for case a).
 

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