vp1953
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Hi Rajesh,
Case 1. Small signal gain is greater than 1 at phase =180. As the input signal increases in magnitude, the gain can come down and even unity gain is possible (when input signal peak to peak value is equal to output voltage swing). Even thought the small signal gain is greater than one, here have a situation for large signals the gain becomes unity. So i think that gain crossover (gain going from greater than 1 to less than 1) happening before phase crossover may not ensure stability.
Case 2. Small signal gain is less than 1 at phase 180. in this case the large signal gain will also be less than 1, no issue here.
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