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From: dad@cs.brown.edu (David A. Durfee)
Newsgroups: sci.electronics
Subject: real inductors
Message-ID: <5290@brunix.UUCP>
Date: 30 Apr 89 20:33:30 GMT
Sender: news@brunix.UUCP
Reply-To: dad@cs.brown.edu (David A. Durfee)
Distribution: usa
Organization: Brown University Department of Computer Science
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I have inherited a circuit which uses an inductor.  Its a
dc voltage converter and the inductor is switched across
5v by a FET so that a higer voltage can be generated across
the inductor.  The inductor catalog shows a maximum DC
current for the part.  Here are my questions (since I don't
know anything about inductors):

1. I'm driving this thing with a square wave and don't see
any current rating for AC.  Should I simply take the average
current and compare that to the max DC rating?

2.What happens when you overdrive an inductor?
I mean regarding modeling its behavior.  Does its resistance
go up and its inductance go down? 

3. MOST IMPORTANT- How will the part degrade over time if
operated beyond its rating?  Will it heat up and break down
its insulation?  Will its inductance value change over time?

(part is 100uH with a Idc Max of 160mA)