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What is operational amplifier?

1 Answer

Operational amplifier is an amplifier which amplifies the input signal when we pass a low voltage signal .It has two terminals inverting and non inverting.

It is an active device because it uses supply to work.

 consider an open loop configuration ( when there is no feedback):

The gain is infinite (according to ideal operational amplifier condition) but practically it is not true. When we provide a  less voltage(~1v)

Then the max voltage which we get at output is the supply voltage provided by us to the operational amplifier (op-amp) but the output waveform is not similar to the input signal (amplified) but in case of negative feedback it provides the output waveform similar to the input waveform (truely amplified )
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