I will use IN 12V out 9V(0.7A)
Is there a minimum OFF time rule for duty?
It looks like about 100ns in LTpowerCAD.
Not really, only to stay in duty range to not violate off-time, on-time limits. For the internal IC the minimum off-time spec'd is 130ns max. (93ns typical). Minimum on-time spec'd is 65ns max…
Thank you for your answer.