[SI-LIST] switching power supply magnetic field emissions and SI problems
- From: Doug Smith <doug@xxxxxxxxxx>
- To: SI-List <si-list@xxxxxxxxxxxxx>, emc-pstc <emc-pstc@xxxxxxxx>
- Date: Mon, 20 Oct 2008 20:10:45 -0700
Hi All,
I have just posted my latest video covering magnetic field emissions from
switching power supplies. Such fields can cause unusual problems in systems
such as data corruption with low enough probability to make finding it
difficult. I have seen such emissions cause data corruption on a tape backup
drive in a computer. It took about an hour for the spikes from a switching
power supply about 12 cm away from the drive to line up with the data
sampling in such a way as to cause a problem. About one read error was made
per hour in a continuous write/read test. Such emissions can also cause
noisein analog circuits and in some cases, as in my new video, even corrupt
digital signals.
The video can be watched in two ways:
Go to http://youtube.com[1] and type dougcsmith in the search field. You
willsee my four videos there, this one being the latest. This video plays in
Flash and is available in low and high resolution versions.
Go to http://emcesd-podcast.com/weekly_podcasts/[2] and click on the "Latest
Show" near the top. This video is in mp4 format, a popular format that has
been around for several years but will not play in Windows Media Player
(every video player I know of will play mp4 except WMP). Quicktime from
Applecan play it as well as the free multi-platform VLC player from
VideoLan.org.
This video shows a great way to find, and even spec for design requirements,
excessive magnetic emissions from switching power supplies that does not
require expensive setups......sort of like the rest of my work on other
problems.
Doug
-- ------------------------------------------------------- ___ _ Doug Smith
\/ ) P.O. Box 1457 ========= Los Gatos, CA 95031-1457 _ / \ / \ _ TEL/FAX:
408-356-4186/358-3799 / /\ \ ] / /\ \ Mobile: 408-858-4528 | q-----( ) | o |
Email: doug@xxxxxxxxxx[3] \ _ / ] \ _ / Website: http://www.dsmith.org[4]
-------------------------------------------------------
--- Links ---
1 http://youtube.com
2 http://emcesd-podcast.com/weekly_podcasts/
3 mailto:doug@xxxxxxxxxx
4 http://www.dsmith.org
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List technical documents are available at:
http://www.si-list.net
List archives are viewable at:
//www.freelists.org/archives/si-list
or at our remote archives:
http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
Other related posts:
- » [SI-LIST] switching power supply magnetic field emissions and SI problems
