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The '''open-loop gain''' of an electronic [[amplifier]] is the [[gain (electronics)|gain]] obtained when no overall [[feedback]] is used in the [[electrical network|circuit]].<ref name=":0" /><ref>{{Cite web |title=Open-Loop Gain - an overview {{!}} ScienceDirect Topics |url=https://www.sciencedirect.com/topics/engineering/open-loop-gain |access-date=2024-10-13 |website=www.sciencedirect.com}}</ref>▼
▲The '''open-loop gain''' of an electronic [[amplifier]] is the [[gain (electronics)|gain]] obtained when no overall [[feedback]] is used in the [[electrical network|circuit]].
The open-loop gain of many electronic amplifiers is exceedingly high (by design) – an ''ideal'' [[operational amplifier]] (op-amp) has infinite open-loop gain. Typically an op-amp may have a maximal open-loop gain of around <math>10^5</math>, or 100 [[Decibel|dB]]. An op-amp with a large open-loop gain offers high precision when used as an [[inverting amplifier]].
Normally, [[negative feedback]] is applied around an amplifier with high open-loop gain, to reduce the gain of the complete [[electrical network|circuit]] to a desired value.
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==Definition==
The definition of open-loop gain (at a fixed frequency) is
:<math>A_\text{OL} = \frac{V_\text{out}}{V^+ - V^-},</math><ref name=":0">{{Cite web |title=Open Loop Gain - Developer Help |url=https://developerhelp.microchip.com/xwiki/bin/view/products/amplifiers-linear/operational-amplifier-ics/introduction/open-loop-gain/ |access-date=2024-10-13 |website=developerhelp.microchip.com}}</ref>
where <math>V^ + -V^-</math> is the input voltage difference that is being amplified. (The dependence on frequency is not displayed here.)
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*[[Negative-feedback amplifier#Summary of terms|Summary of negative feedback amplifier terms]]
==References==
[[Category:Electrical parameters]]▼
{{reflist}}
▲[[Category:Electrical parameters]]
{{Electronics-stub}}
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