Other Parts Discussed in Thread: TPS54561, TPS54561EVM-555
We are planning to use the TPS54561-Q1 for our application to derive 5V from 8V to 13V input.
The output current requirement is 4A & we are planning to re-use the application design provided in the datasheet.
Our design must operate in condition with ambient temperature of -20C to 80C.
1. We had gone through the datasheet & we noted the following was mentioned in "Safe Operating Area" Section.
"Figure 47, through Figure 50 doesn't consider the impact from the catch diode thermal performance"
Was TPS54561 EVM kit with a different diode part (as opposed to PDS760-13 part in application design) used to plot the Safe operating curves?
2. We calculated the diode loss (for PDS760-13 which is used in the application design) with the help of equation 40 in the datasheet for 13V input , 5V 4A output which turns out to be 1.38719W.
With this value, we calculated the max ambient temperature for operation for this diode which came out to be 87.57C (only when considering Rth as 45, refer https://www.diodes.com/assets/Datasheets/PDS760Q.pdf).
Having said, If we closely follow the layout as in the EVM layout design, Will the design work in -20C to 80C ambient range without any issues?
FYI, Our board is going to be mutli-layered board and we expect at least 2 GND planes in our design
Kindly let us know ASAP