I have a different results for LT8643S based step-down converter.
LTpowerCAD report closed loop bandwith 100kHz, LTspice 130kHz.
Which of them can be trusted?
See attachment, please.
Anyway... LTspice FRA settings is very poorly documented, I can not find any application notes or other sourses.
Only single basic and very short information available at
[edited by: Levandovsky at 10:43 AM (GMT -4) on 4 Apr 2023]