D1 Catch Diode Selection - I_f(avg) too low?

[M4a1x]

Hey Phil,

first off: Thanks for the great videos they have been an immense help! I found this board looking for inspirations on the TPS5430 5V/3A power supply, since it's a basic part at JLCPCB.

I noticed that in your design for D1 (didn't look at the split rail regulator) you went with a B5819W 0.6V/1A (max. 40V reverse) Schottky diode, whereas TI suggests in the datasheet (Chapter 8.2.1.2.6) a B340A 0.5V/3A (max. 40V reverse) for their 5V supply, as it "must be greater than I_out".

Since you specified your load to be max. 2.5A I think the Diode might be running out of spec on high loads. I was wondering if e.g. an SS34 (also a basic part) would be a better choice.

I'm no professional though, so if your choice was deliberate I would love to hear about the calculations to understand this better. On this remark, I would love to hear the reasoning why you didn't "just copy" the values from the "Typical Application" of the datasheet (Chapter 8.2.1) - e.g. the 47uH inductor vs the suggested 15uH - if you still remember after all this time.

Thanks for reading :)

Cheers, Max