Page 19 - Semester-IV-Electronics

Operational Amplifiers

 Amplifier having a very high gain with input impedance very large

but output impedance very low.

 With negative feedback, the resultant gain of his amplifier depends

only on the feedback factor, = =

 These are also used comparator, voltage regulator, wave generator

etc. The speciality is that it rejects the unwanted voltage signals.

Characteristic properties of OP-AMP

 Infinite voltage gain

 Infinite bandwidth

 Infinite input impedance

 Zero output impedance

 Perfectly balanced circuit = Both input signals are identical so that

the output voltage is zero.

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