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Date: Wed, 26 Aug 2015 15:03:10 -0400
Message-Id: <201508261903.t7QJ3AJJ005402@envy.delorie.com>
From: DJ Delorie <dj AT delorie DOT com>
To: geda-user AT delorie DOT com
In-reply-to: <1508261840.AA26986@ivan.Harhan.ORG> (falcon@ivan.Harhan.ORG)
Subject: Re: [geda-user] Need help with MOSFET part selection
References: <1508261840 DOT AA26986 AT ivan DOT Harhan DOT ORG>
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Once you've narrowed down the digikey search to n-mosfets in the right
voltage range and allowed packaging, IMHO the key spec to look at is
Vgs(th)@Id since you need a high Id at low Vgs.  Then start narrowing
it down by preference, and look at the Vgs/Id charts in the pdfs for
one that does what you want.  If you have multiple choices, look at
gate charge, since a lower charge puts less load on the input.

The trick is to not narrow down your search too much.  For example,
don't choose a 20mA part because you need 20mA - choose ALL parts that
are 20mA or more (yes, even the multi-amp ones), because sometimes a
larger part fits your needs despite being comically oversized.

If after all that you still have choices, what I do is pick something
cheap that digikey has a lot of :-)