raja.cedt
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hello Summi, Sorry 8 is bit difficult to understand without clear explanation. think about internal loop with op2, assume op2 UGB is wu2, so closed loop 3db BW is wu2/2, now in the overal loop this appers like non-dominate pole so at least wu1(op1 UGB) to be equal to wu2/2 to have 45deg phase margin, so ratio 2 is okay, but if you have wu1=wu2/8 then good PM.
Please go through 2nd order system basics.
Thanks, Raj.
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