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!

Negative Resistance - 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: Negative Resistance Posted: Sun Sep 16, 2007 9:23 am


Joined: Fri Aug 11, 2006 6:07 am
Posts: 5
I'm trying to synthesize a negative resistance to add to a circuit. As far as I know there are three popular ways of doing so:
1. Using a device with negative resistance characteristics (e.g. Tunnel Diode).
2. Using a configuration of OpAmps with feedback that gives a negative resistance when seen from the input.
3. Using a configuration of BJTs, ot FETs.

It is the third method that I'm interested in since I'm working at a somewhat high frequency and I need to be able to integrate the resulting circuit on an IC. I'm specifically interested in making a negative resistance using MOSFETs. I did read a couple of papers that talked about the subject but it was quite general, with no reference to biasing or methods of tuning. While I was able to sucessfully simulate a negative resistance using two MOSFETs, the resulting resistance was quite large (tens of Mega Ohms) and it was unstable when put in a larger circuit.

The resistance I need is S-type, in the range of tens of Ohms. Can anyone point me to where I can get more info on this subject?

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 !