Does NFmin in cascode LNA depend on the negative feedback inductance?

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SUMMARY

The discussion centers on the relationship between NFmin (minimum noise figure) in a cascode Low Noise Amplifier (LNA) and the negative feedback inductance. Participants reference literature suggesting that NFmin remains constant across different configurations. The need for a clear proof of this assertion is emphasized, indicating a gap in understanding among practitioners in the field. The inquiry highlights the importance of theoretical foundations in LNA design.

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  • Understanding of cascode LNA design principles
  • Familiarity with noise figure (NF) concepts
  • Knowledge of negative feedback mechanisms in electronic circuits
  • Ability to interpret technical literature on RF design
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  • Research the mathematical derivation of NFmin in cascode amplifiers
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Electrical engineers, RF designers, and students involved in the design and analysis of Low Noise Amplifiers seeking to deepen their understanding of noise figure optimization.

anhnha
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Hi,
This is a cascode LNA. Please help me with the question in picture. Thank you.

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What are your thoughts on the question? Is this for school?
 
No, I am designing a LNA not a homework.

I read some books and papers saying that NFmin in two cases are equal. However, I would like to understand clearly why and read a decent proof.
Do you have ideal how to prove that?
Thanks.
 
Last edited:

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