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why is it an in-phase zero?

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coolsummer

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The book says: "CFF is to feed forward small signals from Vo to feedback node VFS. This introduces an in-phase zero ZFF that helps save phase near the unitygain frequency of the system. "
But the base of Q1(VA) is inverting input, VA and Vo are out of phase, so CFF should introduce a right-half plane zero, which degenerates the frequency response. Where am I wrong?
 

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CFF is part of the feedback network. I'd call it a lead or lead-lag circuit. It raises the loop phase in a limited frequency interval to increase the phase margin. I think that the term feedforward is misleading in this context. But beyond terms, the circuit surely involves no right half-plane zero.
--- Updated ---

The TI application is discussing a similar setup https://www.ti.com/lit/pdf/sbva042
 
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