Custom Search
Over 9,000 pages indexed!
Your Host
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!)

5CCG (5th MOB):
My USAF radar shop

Hobby & Fun

Airplanes and Rockets:
My personal hobby website

Equine Kingdom:
My daughter Sally's horse riding business website - lots of info

Doggy Dynasty:
My son-in-law's dog training business

•−•  ••−•    −•−•  •−  ••−•  •
RF Cafe Morse Code >Hear It<
Job Board
About RF Cafe©
RF Cafe E-Mail
Product & Service
Directory
Engineering
Jobs
Personally Selected
Manufacturers
Employers Only
(no recruiters)
GSM modules - To supercap or not to supercap.... - 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.


RF Head
Post subject: GSM modules - To supercap or not to supercap.... Posted: Tue May 05, 2009 3:47 am

Captain

Joined: Mon Feb 09, 2009 12:26 pm
Posts: 11
I haven't had to play with GSM stuff for a while so please bear with me. The last time I did delve into this area I went with manufacturers recommendations and added a supercap to the design to keep the supply voltage stable. This was probably using something like siemens MC55.

I recently checked out Telit GE864. There was no mention of any need for very large supercaps, only a 100uF low esr cap.

Just wondered if anyone had any practical experience with the latest GSM modules, most specicically, if they really are ok with a simple 100uF low esr capacitor OR maybe they do need a bit more help?

Of course, battery internal resistance must be considered!

Steve


Top

IR
Post subject: Re: GSM modules - To supercap or not to supercap....Posted: Tue May 05, 2009 4:29 pm

Site Admin


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

I used a GSM/GPRS module in one of my designs.
A low-noise linear regulator will do the work, I checked the datasheet of the Telit GE864, and what they mentioned is OK.

The purpose of Supercapcitor is quite different, it is used in applications with low quiescent currents and where it can be charged for multiple use, instead of using batteries.

_________________
Best regards,

- IR







Posted  11/12/2012

RF Cafe Software

RF Cascade Workbook
RF Cascade Workbook is a very extensive system cascaded component Excel workbook that includes the standard Gain, NF, IP2, IP3, Psat calculations, input & output VSWR, noise BW, min/max tolerance, DC power cauculations, graphing of all RF parameters, and has a graphical block diagram tool. An extensive User's Guide is also included. - Only $35.
RF system analysis including
frequency conversion & filters

Smith Chart™ for Excel
Smith Chart™ for Visio
RF & EE Symbols Word
RF Stencils for Visio

A Disruptive Web Presence

Custom Search
Over 9,000 pages indexed!
Read About RF Cafe
Webmaster: Kirt Blattenberger
KB3UON

Product & Service Directory
Personally Selected Manufacturers

RF Cafe T-Shirts & Mugs
Calculator Workbook
RF Workbench
Please Support My Advertisers