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SOA calculations using ADM1270 for 40A inrush current

I have an application where I am controlling Inrush current of 40Amps; To control this I am using ADM1270 IC. This can be understood by following block diagram.






I have issue in Timing parameters to calculate capacitor values.

My spec are mentioned below

  1. Vdc min.=16V
  2. Vdc max=32
  3. Vdc nom=28V
  4. Idc max =3.33A@16V
  5. Inrush current by EMI Filter and Converter = 40A
  6. Output capacitor= 100-500uF(After Filter and Converter)
  7. Amb Temp.=71°C
  8. Power Good threshold=16
  9. Voltage Foldback=15.2
  10. UV=10% of 16V
  11. OV=10% of 32
  12. RPOWERUP = don’t know (static load resistance during system power up)?
  13. P channel Mosfet Used to suit design is SPB80P06P G

Vds=-60V;Ids=-80A;Rdson=23mΩ @ 25°C and 36mΩ @ 150°C;θja=60K/W and θjc=0.6K/W


I did not get following things

  1. MOSFET SOA Analysis – Short Circuit
  • Graph of Op voltage Vs Power Dissipation
  • Vout_wcp
  • How it is going to protect by Short ckt operation
  • How it is protecting converter and filter by 40A Inrush Current.
  • In spread sheet and Datasheet Inrush Value is not considered.
  • But I have to protect my converter and filter by 40A inrush current.
  • Kindly help me for these calculations in detail