vivkr
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Hi,
Pole splitting will occur only when the dominant pole is set by the compensation capacitance Cc. If you increase the value of this cap from zero to a certain optimum value, the dominant pole will rapidly move lower and lower, while the nondominant pole will move outwards. Beyond a certain point, increasing Cc will not cause the nondominant pole to move further or not much further. The second pole is set at Gm2/Cl. After this point, you need to increase Gm2 to move the second pole out.
Note in particular that it is highly undesirable practice in general to go on increasing Cc, and Cc >= Cl will give diminishing returns. In a good design, Cc < Cl and preferably by a factor of 2-3. Otherwise, you are wasting power. In some exceptional cases (very low-bandwidth circuits), you may want to increase Cc a lot to reduce total inband noise. That's it.
Vivek
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