comparator in closed loop: op-amp or standard comparator?

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allennlowaton

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Good day guys..please shed some light regarding this one.
From the figure below, I would like to ask some suggestions whether I'm going to use a compensated OP-amp or a standard comparator.
Also, I believe that the comparator below forms a closed loop. If I'm going to use a standard comparator, do I need to compensate it?
By the way, my input signals are digital pulses

Thank you.

 

The input signals to the comparator in a current-mode buck converter are not digital pulses. But it's correct to use a comparator in this place, and you should not compensate it rather than make it fast. The output of the comparator is in fact a "digital" on-off signal, what should be the purpose of compensating a comparator? There's no analog feedback from the comparator output, the logic controlled by the comparator is acting digital anyway.
 
thank you FvM.
can I use a cross coupled and diode connected comparator? what is it advantage as compared to using the simple comparator?
 

it is a buck converter. Comparator should be faster as possible, compared with switching frequency. The loop compensation is not for comparator, while could be considered as Switching System stablity. Refer some about Buck converter, which would help to understand more.
 
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