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yungman
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This in not homework. I am playing with this circuit and I don't understand what is not right. Here are the circuits.
a) I "built" an opamp out of U6, U7 and U8. I set the gain to 21 by R6/R3+1=20+1=21. The output is OUT1. But I get a little more gain than expected, like 22 or 23.
b) I use U1 as reference as set gain = R4/R5 + 1 = 21, the output is OUT2.
The signal generator is V10, frequency is 1KHz, 0.1Vpeak. You can see the graph OUT2 ( red) is correct at 21, and OUT1(green).
Am I thinking wrong that this is not the right way to do feedback?
Thanks
Alan
a) I "built" an opamp out of U6, U7 and U8. I set the gain to 21 by R6/R3+1=20+1=21. The output is OUT1. But I get a little more gain than expected, like 22 or 23.
b) I use U1 as reference as set gain = R4/R5 + 1 = 21, the output is OUT2.
The signal generator is V10, frequency is 1KHz, 0.1Vpeak. You can see the graph OUT2 ( red) is correct at 21, and OUT1(green).
Am I thinking wrong that this is not the right way to do feedback?
Thanks
Alan
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