What are the benefits of using a permanent magnet for a coil core. I recently came across a design for a switching power supply that used magnets as cores for the inductor. I have never heard of such a thing, except maybe in speakers.
Permanent magnets as coil cores?
May 12, 2008
5 Replies
If there is DC current flowing in the coil, it reduces the amount of flux "swing" that can happen without saturating the core. Or looking at it from another angle, you need a physically larger (more $$) core to do the same AC work if it is also carrying DC. Using a permanent magnet to counteract the DC flux allows a smaller (cheaper) part to be used. Used to see these in the vertical section of TV's in the days before power IC's.
Your use of Usenet
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needs improvement.
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*-*-*-marked-as-Read-in-ALL-*-groups+Newsgroups.line More here:
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I suspect it was the horizontal, not the vertical, circuit, and its purpose is to provide two different inductances, one for "positive" currents, and a different one for "negative" currents. Those are used to provide linearity correction.
Isaac
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*-*-*-*-*-*-*-*-appear+*-proper-answer-*-*-*-given+much-easier-*-*-*-*-*-*-*+*-frowned-on+*-correcting+*-Followup-To-*+*-*-_perfect_-*-*-*-*+*-*-*-too-lazy-*-*-*-*-*-appropriate-*+*-polite-*-mention-*-*-*-*-*-*-*+Just-because-*-*-*-*-*-*-*-*-does-not-mean-*-*-*-*-*-*+mark-*-*-*-*-all-*-groups+*-*-*-*-two-groups-*-*-aren't-*-different
Why don't you find the person's email and send to them directly? There's a much greater chance that they will see your response.
Your repeated posts about multi-posting take more bandwidth than the people you are faulting.
Get a life...
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