•−•  ••−•    −•−•  •−  ••−•  •
RF Cafe Morse Code >Hear It<
Job Board
About RF Cafe™
Copyright 1999-2015

Question on biasing circuitry - RF Cafe Forums

Because of the high maintenance needed to monitor and filter spammers from the RF Cafe Forums, I decided that it would be best to just archive the pages to make all the good information posted in the past available for review. It is unfortunate that the scumbags of the world ruin an otherwise useful venue for people wanting to exchanged useful ideas and views. It seems that the more formal social media like Facebook pretty much dominate this kind of venue anymore anyway, so if you would like to post something on RF Cafe's Facebook page, please do.

Below are all of the forum threads, including all the responses to the original posts.

Post subject: Question on biasing circuitry Posted: Tue Apr 25, 2006 2:14 am


Joined: Tue Apr 25, 2006 2:01 am
Posts: 7
I am noticing a difference in the overall gain (of an LNA) depending on where the off-chip decoupling capacitors are placed (close to or away from the chip). Any ideas on why this might be happening?


Post subject: LNA bypassingPosted: Tue Apr 25, 2006 5:36 pm


Joined: Wed Feb 22, 2006 3:51 pm
Posts: 104
Even a short trace on a PCB looks like a non-negligible inductor at a high-enough frequency. So a bypass capacitor away from the chip might even look inductive, depending on the length of pcb trace and the operating frequency. That would give unintended feedback via the power supply pin of the IC, which would affect the gain.

Good Luck!

Posted  11/12/2012
Custom Search
More than 10,000 searchable pages indexed.

Your RF Cafe
Progenitor & Webmaster

Click here to read about RF CafeKirt Blattenberger... single-handedly redefining what an engineering website should be.

View the YouTube RF Cafe Intro Video Carpe Diem!
(Seize the Day!)

5th MOB: My USAF radar shop

Airplanes and Rockets: My personal hobby website

Equine Kingdom: My daughter Sally's horse riding website