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School Project Help.

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I need a little advise for a little project.

I need to build a smart(with automatic gain control) amplifier with the following characteristic:

When the output voltage swing exceeds an external limit set by the user (Vref), amplifier decreases its gain such that the output voltage swing remains aroud Vref.

The circuit is supposed to be operating up to 20 kHz and maximum gain should be 40.
Supply voltages are +5 and -5 volts.
Min Vref=100mV and maximum deviation can be 5%.

Thank you for your help.

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On 2/13/2022 at 7:14 PM, M Salman Sarwar Khan said:

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Implement feedback using an optical element, such as a photoresistor, which will adjust the gain depending on the output voltage. Connect the photoresistor to the inverse input of the op-amp through a voltage divider. When the output voltage swing exceeds the set Vref, the photoresistor will change its resistance, which will affect the feedback and reduce the amplifier gain. I also didn’t understand this before and often pay for homework, I found https://ca.edubirdie.com/pay-for-homework for this. But I realized that this is not entirely profitable. And also, do not forget to take into account the minimum value of Vref and its deviation of 5%. Use an op-amp with high gain and built-in overload protection. Good luck with the project!

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