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Razavi motivated the design of the Gain-Boosting configuration by stating that,

The limited gain of the one-stage op-amps studied in Sec. 9.2 and the difficulties in using two-stage op-amps at high speeds have prompted extensive work on new topologies.

enter image description here I have tried to Google the reason why it is difficult to use two-stage op-amps at high speeds, but haven't found any explanation. For engineers with experience in designing high-speed amplifiers, could anyone provide an explanation or a reference related to this question?

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    \$\begingroup\$ Consider the effect of the dominant poles from each stage. \$\endgroup\$ Feb 20 at 12:28

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Two-stage (and also three- or more-stage) amplifiers have more phase shift and higher open-loop gain, which makes it more difficult to apply negative feedback in a stable manner.

And this feedback is usually required for reasons including - but not limited to - getting a well-determined gain level, a specific filter behavior, to reduce distortion, or to create the desired input and output impedances.

PS: also for obtaining the desired DC operating point. (As I said: not limited to what I already mentioned...)

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