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From: jgk@osc.COM (Joe Keane)
Newsgroups: sci.electronics
Subject: Re: A question about effect of offset voltage in trans-amps
Summary: Don't divide by the gain.
Keywords: feedback, offset
Message-ID: <4860@osc.COM>
Date: 22 May 91 21:38:56 GMT
References: <2644@pdxgate.UUCP>
Reply-To: Joe Keane <jgk@osc.com>
Organization: Versant Object Technology, Menlo Park, CA
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It is true that output offset is much less when using a follower configuration
than just open-loop.  However, note that offset is almost always referred to
the input.  In the follower the input offset and output offset are the same,
so you just use that number.  In the open-loop situation the input offset must
be _multiplied_ by the gain to get the correct output offset.
--
Joe Keane, amateur electronics hacker
jgk@osc.com (...!uunet!stratus!osc!jgk)