EMB1499Q: Application note SLUUAS6A query

Hi

I have two queries about SLUUAS6A need your help. 

1, From the application note 5.11.2 Loop Stability, How to define  dt and AI value?

2, From 5.6 Active-Clamp Driver Circuit, why to use U1,U2 in Figure 5-7? Is it possible to add a delay circuit? 

Waiting for your reply.

Thanks

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