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The open-loop gain is a physical attribute of an operational amplifier that is often finite in comparison to the ideal gain. While open-loop gain is the gain when there is no feedback in a circuit, an operational amplifier will often be configured to use a feedback configuration such that its gain
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The open-loop gain can be important for computing the actual gain of an operational amplifier network, where the assumption of infinite open-loop gain is inaccurate.
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Take the case of an inverting operational amplifier configuration. If the resistor between the single output node and the inverting input node is
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is the input voltage difference that is being amplified. (The dependence on frequency is not displayed here.)
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156:(op-amp) has infinite open-loop gain. Typically an op-amp may have a maximal open-loop gain of around
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576:{\displaystyle G={\frac {-{\frac {R_{2}}{R_{1}}}}{1+(1+{\frac {R_{2}}{R_{1}}}){\frac {1}{A}}}}}
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is applied around an amplifier with high open-loop gain, to reduce the gain of the complete
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The open-loop gain of many electronic amplifiers is exceedingly high (by design) – an
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The open-loop gain of an operational amplifier falls very rapidly with increasing
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and the resistor between a source voltage and the inverting input node is
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278:{\displaystyle A_{\text{OL}}={\frac {V_{\text{out}}}{V^{+}-V^{-}}},}
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The definition of open-loop gain (at a fixed frequency) is
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will be controlled by the feedback circuit components.
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756:Summary of negative feedback amplifier terms
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440:{\displaystyle G=-{\frac {R_{2}}{R_{1}}}}
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114:Learn how and when to remove this message
626:{\displaystyle {\frac {R_{2}}{R_{1}}}=2}
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773:This electronics-related article is a
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48:adding citations to reliable sources
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321:{\displaystyle V^{+}-V^{-}}
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176:{\displaystyle 10^{5}}
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104:December 2009
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59:Find sources:
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779:expanding it
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42:Please help
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818:Categories
206:Definition
194:Normally,
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750:Loop gain
733:bandwidth
729:slew rate
725:frequency
490:−
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183:, or 100
132:amplifier
31:does not
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134:is the
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52:removed
37:sources
288:where
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151:ideal
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633:and
136:gain
126:The
67:news
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33:cite
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