The Cyber-Spy.Com Usenet Archive Feeds Directly
From The Open And Publicly Available Newsgroup
This Group And Thousands Of Others Are Available
On Most IS NNTP News Servers On Port 119.
Cyber-Spy.Com Is NOT Responsible For Any Topic,
Opinions Or Content Posted To This Or Any Other
Newsgroup. This Web Archive Of The Newsgroup And
Posts Are For Informational Purposes Only.
X-Mailer: Mozilla 4.79 [en] (Win98; U)
Subject: Re: Core gapping techniques and general SMPS magnetics stuff
NNTP-Posting-Date: Sun, 15 Dec 2002 06:42:02 GMT
Organization: AT&T Broadband
Date: Sun, 15 Dec 2002 06:42:02 GMT
Mike Engelhardt, Chris Carlen wrote:
>> So I will have to gap my cores. How do you folks gap E-cores for
>> prototype/low volume applications?
> Shims work and even, unforturnately, get into production sometimes.
> I had a Lambda SMPS with shims in the outer legs. But the fringe
> fields interfered with the the scanning electron microscope it was
> powering so I swapping out that power supply with one that had used
> properly gapped magnetics, i.e., a gap only in the center.
A distributed gap (which is better approximated by gapping all three
legs) will fringe less into the windings and will generally lead to
better performance in flyback applications. Usually a shorted turn
around the outside of the core in the form of a band of copper tape
will suffice to contain external leakage fields it that is a problem.
However, if you do this, be sure to space the band at least two or
three gap lengths away from the core in the vicinity of the gap in
order to avoid inducing excessive eddy currents in the copper band.
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup