Thank you for visiting RF Cafe! Electronics World Cover,TOC,and list of posted Popular Electronics articles QST Radio & TV News Radio-Craft Radio-Electronics Short Wave Craft Wireless World About RF Cafe RF Cafe Homepage RF Cafe in Morse Code Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs Twitter LinkedIn Crosswords Engineering Humor Kirt's Cogitations Engineering Event Calendar RF Engineering Quizzes AN/MPN-14 Radar 5CCG Notable Quotes App Notes Calculators Education Magazines Software,T-Shirts,Coffee Mugs Articles - submitted by RF Cafe visitors Simulators Technical Writings RF Cafe Archives Test Notes Wireless System Designer RF Stencils for Visio Shapes for Word Search RF Cafe Sitemap Advertising Facebook RF Cafe Forums RF Cafe Homepage Thank you for visiting RF Cafe!

LNA Help!!! - RF Cafe Forums

The original RF Cafe Forums were shut down in late 2012 due to maintenance issues. Original posts:

Amateur Radio | Antennas | Circuits & Components | Systems | Test & Measurement

Post subject: LNA Help!!!
Unread postPosted: Thu Jul 14, 2005 10:27 am

Joined: Mon May 30, 2005 9:16 am
Posts: 1
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.




Post subject:
Unread postPosted: Thu Jul 14, 2005 10:49 am
Site Admin
User avatar

Joined: Mon Jun 27, 2005 2:02 pm
Posts: 373
Location: Germany
Hello Ginevra,

First of all, you will need to select a transistor matching for your frequency band and gain.

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): ... torial.pdf

Should you need additional help, please let me know.

Good luck!! :wink:

Best regards,

- IR


Post subject:
Unread postPosted: Thu Jul 14, 2005 11:41 am

Dear IR,

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

Posted  11/12/2012

RF Cafe Software

   Wireless System Designer - RF Cafe
Wireless System Designer

RF & EE Symbols Word
RF Stencils for Visio
Calculator Workbook
RF Workbench
Smith Chartâ„¢ for Visio
Smith Chartâ„¢ for Excel

About RF Cafe

Kirt Blattenberger - RF Cafe WebmasterCopyright
1996 - 2022
Kirt Blattenberger,

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:

Try Using SEARCH
to Find What You Need. 
There are 1,000s of Pages Indexed on RF Cafe !