CMOS low noise amplifier reference suggestions

Thread Starter

Minchuu

Joined May 13, 2021
17
Hello,

I want to design a CMOS Low Noise Amplifier for the frequency range 0.65 MHz to 1.45 MHz with: less than 3dB NF, ~10 dB power gain, greater than -5 dBm IIP3, and input and output impedance of 50 ohms.

I am searching for references (books, sites, articles etc.) that can guide a beginner like me to build one. It would be preferable if it is easy to understand and outlines a clear step-by-step guide like a recipe book.

Thank you very much.
 

Papabravo

Joined Feb 24, 2006
17,316
Hello,

I want to design a CMOS Low Noise Amplifier for the frequency range 0.65 MHz to 1.45 MHz with: less than 3dB NF, ~10 dB power gain, greater than -5 dBm IIP3, and input and output impedance of 50 ohms.

I am searching for references (books, sites, articles etc.) that can guide a beginner like me to build one. It would be preferable if it is easy to understand and outlines a clear step-by-step guide like a recipe book.

Thank you very much.
The things you seek may or may not exist. If they don't then you have wasted a great deal of time on a fruitless pursuit. You don't necessarily get a recipe for every task you are assigned. What is the best you can do without one? Can you meet any of the requirements?
 

Thread Starter

Minchuu

Joined May 13, 2021
17
The things you seek may or may not exist. If they don't then you have wasted a great deal of time on a fruitless pursuit. You don't necessarily get a recipe for every task you are assigned. What is the best you can do without one? Can you meet any of the requirements?
Hello, thanks for the reply. I looked at the available topologies and I think the best is the Cascode with Inductor degeneration. Actually, I think this will fit my application the best but it is in 2.4 GHz. I really really tried searching what are the equations needed to compute for the components so I can change the components to fit the schematic design but it is severely distorted at 0.65 MHz to 1.45 MHz. The frequency range I have is too small for any of the resources I can find in Google when I search for LNA because it is usually in Gigahertz.

Even telling me what components to change here and what equation I should use to compute for the new ones will be very much appreciated.

Thank you very much!
 

Papabravo

Joined Feb 24, 2006
17,316
Hello, thanks for the reply. I looked at the available topologies and I think the best is the Cascode with Inductor degeneration. Actually, I think this will fit my application the best but it is in 2.4 GHz. I really really tried searching what are the equations needed to compute for the components so I can change the components to fit the schematic design but it is severely distorted at 0.65 MHz to 1.45 MHz. The frequency range I have is too small for any of the resources I can find in Google when I search for LNA because it is usually in Gigahertz.

Even telling me what components to change here and what equation I should use to compute for the new ones will be very much appreciated.

Thank you very much!
There might be a reason why you can't find any reference material for that frequency range since it covers a considerable chunk of the AM broadcast band (530 kHz to 1640kHz). I'm not aware of any LNA applications in this segment of the RF spectrum that would not be covered by a run of the mill RF amplifier. The level of atmospheric noise propagating over long distances makes such a thing impractical. LNAs are used with highly directional antennas, with a small aperture to eliminate much of the noise from all sources.

Since this is Homework Help you need to take your best shot and we can help you with that. On top of that, since this is a kind of impractical problem (IMHO), I don't have a ready solution that I can trot out. Even if you can't meet all of the requirements, you should get credit for meeting some of them and maybe that is the point of the exercise - to give you a problem that you must solve on your own because there are no accessible ready made solutions out there. So just pretend it is 1920 and the relevant papers and research materials have not yet been produced, but you have access to a marvelous set of experimental tools.
 
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Thread Starter

Minchuu

Joined May 13, 2021
17
Since this is Homework Help you need to take your best shot and we can help you with that. On top of that, since this is a kind of impractical problem (IMHO), I don't have a ready solution that I can trot out. Even if you can't meet all of the requirements, you should get credit for meeting some of them and maybe that is the point of the exercise - to give you a problem that you must solve on your own because there are no accessible ready made solutions out there. So just pretend it is 1920 and the relevant papers and research materials have not yet been produced, but you have access to a marvelous set of experimental tools.
This makes sense, thank you for that :) I will try to simulate one model and see where I will get with there. I got too caught up finding references but you are right, I can experiment. Thanks!
 
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