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Johnny was quoting me there, he asked "can't the output drift negative?" I was just trying to point out that there is really no way to answer that question. Output of what? A triode? A single (positive) supply discrete transistor design? A single supply op-amp design? Then no. A dual supply design? Depends, is it discrete transistors, all NPN? Maybe, if the input is tied to 0V and you have several BE drops in series, sure, output would be negative.
If the circuit uses op-amps does the input pair always need bias current in a particular direction? If so that might develop an offset voltage across the input bias resistors that is always in the same direction. If the op-amp is FET input then there typically isn't a predictable DC bias current.

So I stand by my original answer, without context of a specific circuit to discuss there is no way to give a sensible (short) answer.

Drip questions

Abbey knows what Drip questions are.

Seems you were lucky to not get pulled into those threads.

<blockquote data-quote="ccaudle" data-source="post: 1123637" data-attributes="member: 41159">Johnny was quoting me there, he asked &quot;can&#039;t the output drift negative?&quot;&nbsp; I was just trying to point out that there is really no way to answer that question.&nbsp; Output of what?&nbsp; A triode?&nbsp; A single (positive) supply discrete transistor design? A single supply op-amp design?&nbsp; Then no.&nbsp; A dual supply design?&nbsp; Depends, is it discrete transistors, all NPN?&nbsp; Maybe, if the input is tied to 0V and you have several BE drops in series, sure, output would be negative.&nbsp; If the circuit uses op-amps does the input pair always need bias current in a particular direction?&nbsp; If so that might develop an offset voltage across the input bias resistors that is always in the same direction.&nbsp; If the op-amp is FET input then there typically isn&#039;t a predictable DC bias current.So I stand by my original answer, without context of a specific circuit to discuss there is no way to give a sensible (short) answer.<a href="https://groupdiy.com/search/228844/?q=Drip&amp;c[title_only]=1&amp;o=relevance" target="_blank">Drip questions</a>Abbey <a href="https://groupdiy.com/threads/drip-drip-drip.78737/post-1008202" target="_blank">knows what Drip questions are.</a>Seems you were lucky to not get pulled into those threads.</blockquote>

[QUOTE="ccaudle, post: 1123637, member: 41159"] Johnny was quoting me there, he asked "can't the output drift negative?" I was just trying to point out that there is really no way to answer that question. Output of what? A triode? A single (positive) supply discrete transistor design? A single supply op-amp design? Then no. A dual supply design? Depends, is it discrete transistors, all NPN? Maybe, if the input is tied to 0V and you have several BE drops in series, sure, output would be negative. If the circuit uses op-amps does the input pair always need bias current in a particular direction? If so that might develop an offset voltage across the input bias resistors that is always in the same direction. If the op-amp is FET input then there typically isn't a predictable DC bias current. So I stand by my original answer, without context of a specific circuit to discuss there is no way to give a sensible (short) answer. [URL='https://groupdiy.com/search/228844/?q=Drip&c[title_only]=1&o=relevance']Drip questions[/URL] Abbey [URL='https://groupdiy.com/threads/drip-drip-drip.78737/post-1008202']knows what Drip questions are.[/URL] Seems you were lucky to not get pulled into those threads. [/QUOTE]

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