Operational amplifier

An operational amplifier or op-amp is a very high-gain amplifier which has two inputs, one inverting (−) and one non-inverting (+). The output voltage is the difference between the + and − inputs, multiplied by the open-loop gain:

Related Topics:
Gain - Amplifier - Open-loop

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:V_mathrm{out} = (V_+ - V_-) cdot G_mathrm{openloop}

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The amplifier's output can be single-ended or, less often, differential. Circuits using op-amps almost always employ negative feedback. Because the op-amp has such high gain, the behavior of the amplifier is almost completely determined by the feedback elements.

Related Topics:
Negative feedback - Feedback

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