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There is one question for NXP related to the actual value of pt1 (row 7, column E of the spreadsheet). Based on MPC5777C datasheet data for power dissipation 1.6W (table 24 of MPC5777C datasheet) and junction temperature (Table 55 of MPC5777C datasheet) for a unit the value of the value of pt1 should be ~ 2. Can you explain how you got a value of 1.53 for pt1 using IEC TR 62380 7.3.1 (which is the standard called out in the comment on cell A1)?
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Hi David
The pt1 is temperature stress factor that is calculated based on TR62380. It is calculated using this equation
exp (3480* [(1/328) - 1/(273+t1+power_dissipation*Rj*0.001))
So the value for power_dissipation=1000mW, T1=40C and Rj = 28.8 is 1.53
Hope this helps you to check the calculations. Let me know if you still see issues.
Regards
-Aarul

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Hi David
The pt1 is temperature stress factor that is calculated based on TR62380. It is calculated using this equation
exp (3480* [(1/328) - 1/(273+t1+power_dissipation*Rj*0.001))
So the value for power_dissipation=1000mW, T1=40C and Rj = 28.8 is 1.53
Hope this helps you to check the calculations. Let me know if you still see issues.
Regards
-Aarul

