Selecting a power supply for a DC DC converter

[diracshore]

Hi all,

I have a PCB with this DC-DC converter I am trying to find a power supply for.

Is it better to supply a lower or higher voltage in the stated input range ? Or does it not matter at all ?

Which of these is more suitable ?

http://www.ebay.com/itm/48V-DC-7-3A-350W-Regulated-Switching-Power-Supply-Fast-from-USA-41-56V-/160691584377

http://www.ebay.com/itm/32V-40V-Adjust-DC-9-7A-350W-Regulated-Switching-Power-Supply-Quality-from-USA-/160691581782

Or is there another product I should be looking at ?

If you would like context on the project,

https://www.eevblog.com/forum/general-pcbedacad-discussions/pcb-with-virtex-5-fpga%27s/

Thanks !

[mobbarley]

It shouldn't matter. its rated at 38-55v, anything in that range with enough current capability should be fine.
I would be going with 48V as it is very common, and it is in the upper middle of the input voltage range - likely to be more efficient too.

[Zero999]

This sounds like a waste of time to me, rather than buying a power supply to work with this DC-DC converter, you should buy a 12V 20A power supply and be done with it.

[markus_b]

Your power supply is likely designed for telecom applications. 48V is the standard telecom supply voltage and there is a lot of equipment designed for it. You'll find plenty of power supplies for 48V, just google it.

I sort of agree with Hero999, if your objective is to get to 12V, then a 12V supply costs the same or is cheaper than a 48V supply. Mostly because 48V has mostly industrial applications, where for12V you'll find lots of consumer stuff too.

Your best bet may be to sell it on Ebay...

[diracshore]

Perhaps, but I'm way too curious now.

The reason I don't bypass the converter is because there are other converters on the board sharing the input line and I also want to power them. I think you are right it is quite probably telecom equipment, 48v is correct.

With this power supply though I am wondering what use it was designed for. The store sells equipment for cars and trucks. Is the output of this supply stable enough for digital equipment ? There is a long list of specs on the page but I'm not sure which are relevant.


http://www.ebay.com/itm/48V-DC-7-3A-350W-Regulated-Switching-Power-Supply-Fast-from-USA-41-56V-/160691584377