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Noise in 2 stage opamp

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Chinmaye

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I have built differential input and differential output 2-stage opamp with open loop Low-frequency gain of 60 dB and UGB 600MHz. I have tried to build a closed-loop amplifier of 6DB using feedback resistors. When i do a noise analysis on the op-amp in LT spice, I get a curve as attached. Can someone explain to me why I am getting this?
 

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  • opamp noise.pdf
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Looks like unsufficient phase margin at loop unity gain frequency with respective gain peaking. Look at closed loop bode plot first. You should have > 60° phase margin to avoid it.
 

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