Among the choices, what is a realistic value for the open-loop voltage gain of an operational amplifier________________?
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Answer: D. 100,000
Explanation
Standard general purpose operational amplifiers are manufactured with extremely high internal open loop voltage gains. An open loop gain value of one hundred thousand ensures precise performance when external feedback components are added. Manufacturers design these multi stage differential amplifiers to provide maximum raw amplification before feedback application. The 741 operational amplifier is a classic industry standard device featuring high input impedance and voltage gain. Open loop gain refers to the amplification factor of the amplifier without any external feedback loop connected. High internal gain allows designers to use simple external resistor networks to set exact closed loop gains.
An open loop gain of one would provide no amplification making the operational amplifier entirely useless. A gain of two thousand is too low for standard general purpose operational amplifier performance specifications. Eighty decibels converts to a voltage gain of ten thousand which is below typical open loop values.
- Subject
- Engineering
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- Electrical Engineering
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- medium
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