LNA Help!!! - RF Cafe Forums
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Post subject: LNA Help!!!
Unread postPosted: Thu Jul 14, 2005 10:27 am
Joined: Mon May 30, 2005 9:16 am
I'm a gilr who isn't able to design a LNA for
ZigBee application at University.The constraints are: Vcc = 1.8V, frequency = 915MHz NF lower as possible,power
consumption as well . Could you give me the formulas and one simple (single ended input, differential output)
circiut. Please could you give me any suggestions ? I really need it.
Unread postPosted: Thu Jul 14, 2005 10:49 am
Joined: Mon Jun 27, 2005 2:02 pm
First of all, you will need to select a transistor matching for your frequency band and
There are plenty of formulas to use when you design an LNA: Stability, Gain, Return Loss, Noise
Figure etc. Nowadays, Engineers mostly use CAE (Computer Aided Engineering) tools for designing LNA, Filter and
other RF circuits. All of these formulas are entered into the design tool and by that save the designer lot of
time and calculations.
Attached is a link to a PDF that will certainly give you a good staring point to
design your LNA (It includes a discussion about the design and formulas involved in LNA design):
Should you need additional help, please let me know.
Good luck!! :wink:
Unread postPosted: Thu Jul 14, 2005 11:41 am
Firstly, I have to thank you, I'm reading
your link and I think it will be useful.
Secondly, I have to use a CMOS or TSMC 0.18um tecnology, input
matching 50 ohm. Do you have any documents about CMOS LNA?
Finally, it is possible to show a circiut in the
topic reply without to have a web space?
Thank you again