Copyright: 1996 - 2024
BSEE - KB3UON
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GSM modules - To supercap or not to supercap.... - RF Cafe Forums
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Below are the old forum threads, including responses to the original posts.
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Post subject: GSM modules - To supercap or not to supercap....
Posted: Tue May 05, 2009 3:47 am
Feb 09, 2009 12:26 pm
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
Re: GSM modules - To supercap or not to supercap....Posted: Tue May
05, 2009 4:29 pm
Joined: Mon Jun 27, 2005
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.