Re: Filter Choke Design

To: tesla-at-grendel.objinc-dot-com
Subject: Re: Filter Choke Design
From: "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz>
Date: Thu, 7 Mar 1996 08:22:28 +1200
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Hi all,
        I just saw a note on SMPS cores and would like to add a bit of
information. The high permeability core used for the input common-mode
filter is a sure-fire to saturate with a fairly low ampere-turns 
applied. Jim explained the way these chokes are wound. They are used
to reject noise appearing on both the windings and therefore have a
high initial permeability to obtain high inductance with only a few
turns. IMO they are totally unsuitable for Tesla filtering. 
   The iron-powder cores (low permeability) on the other hand would 
be far better for our application IMO. However, they do require a lot 
of turns to get a reasonable inductance.

Penny in the slot,
Malcolm