non-isolated AC-DC Converter limit inrush current

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Hello,

I tried to design a Buck with Viper. But now I have some problems selecting the right Components.

Can sombeody help me finding right Component for Rin? (13Ohm)? How much power have Rin to dissipate? Can also somebody help me in estimating inrush current? Inrush current should be smaller than 500mAmps (e.g. max 400mA).

I tried to simulate in LT-Spice but the simulation didnt work...Thanks for your help!