Hi team,
I wonder what RGW package is and its advantage over the other packages when it comes to TPS74401. Plus, can you kindly let me know how I get information about overall package types that are provided in TI? It's always confusing and hard to catch the advantage of each package type when I suggest them to customers. Thank you so much!
Hi Minkyung,
Other than the obvious size difference:
The real difference between the packages other than size is thermal performance as shown below:
Here the lower the number the better as this helps to predict the thermal rise on the PCB. The way to use this is the just take your worst-case power dissipation which is (VIN-VOUT)*ILOAD_MAX. This is the maximum power dissipation in Watts (W). So this number times TJA would be the temperature rise above PCB ambient.
For example, if you have VIN at 3.3V and VOUT is 2.8V, and your maximum load current is 2A, then you have (3.3-2.8)*2 or 1W of power dissipation. If you pick the RGR package, then it has a TJA of 39.1C/W.
So 1W*39.1C/W is a 39.1C degree rise above ambient. Meaning if the worst-case ambient of your PCB is 40C, then the die junction temperature would be 40C+39.1C or 79.1C.
Keep in mind that the thermal parameter metrics we provide are based on a JEDEC standard High-K PCB which actually is not an ideal layout as highlighted in the following application note.
I hope this helps to clarify.
