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You can get 48V DC -> 5V DC 6.5A converters that are 92% efficient [1]

You're dissipating 25W from your SBC already. You can dissipate the 2W from your DC-DC converter the same way.

[1] https://www.meanwellusa.com/webapp/product/search.aspx?prod=...




> current range 0 ~ 6.5A

> Fuse recommended (5A)

I see they are very confident about going to 6A. These ratings are often just "yeah it can technically do that but it will reach 100 degrees during it", for any kind of stable continuous draw you just have to halve the rating to be safe.


If you want you can buy the next size up [1] giving you 11A at 5V with the same 92% efficiency.

Of course, it'll still dissipate the same amount of power, because 8% of 25W is still 2W.

[1] https://www.meanwellusa.com/webapp/product/search.aspx?prod=...


That looks more like it (8A fuse), and relatively cheap on Mouser too interestingly enough. Thanks for the heads up I'll have to order and try one.

It does puzzle me why they went with the 2.54mm pin layout though, those are rated for 3A max I think? So even if the draw is perfectly split between the two vout pairs they give it'll be melting at 6A already, probably more like 5 if not.


I know the pin looks small compared to the cable you'd run to a wall socket for a 10A current - but those cables are a lot longer these copper pins, and cables are sized with the assumption the copper will be coated in insulation then coated in another layer of insulation then installed into a wall full of insulation.

A 10mm copper pin measuring 0.6mm x 0.6mm pin would have half a milliohm of resistance. Even if you ran your entire 5A load through a single pin, it would only have to dissipate 13 milliwatts.

I'd be more worried about the PCB traces if I were you - 2oz copper is only 0.07mm thick :)




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