Power Conversion: 24 vdc at .35 A to 12 vdc at 2 A

Other Hardware General Electronics
1

Hi all,

Have a quick question about power conversion. I need to take the juice from a Power-over-Ethernet line that runs at 48vdc/.35A, and convert it to 12vdc/2A. I've found some off the shelf converters that do (48vdc/.4A)-(12vdc/1A) or (5vdc/2.5A). Obviously, the amperage on the 12vdc conversion won't cut it for my needs. It's also worth noting that I will need a 5vdc/1.2A line for another device. I'm a little worried about the excess amperage there, but think it should be okay. Please advice if I should be more concerned about this aspect.

In short, I'm looking for either an off-the-shelf converter that can meet my requirements or a circuit that I can easily build and deploy.

Thanks for your time and responses!

2

Let's see. You want to put 48v x .35A = 16.8w into a box and get 12v @ 2A = 24w out.

Neat trick. If you figure out how to do that then we can solve the world's energy crisis.

3

I was really hoping that I would get a snarky response. Thanks! ]:smiley:

4

Power out = power in less some loss.
You need a heftier source, no way around that.

5

Understood, CR. It turns out that the PoE switch can kick out 30 Watts max. I don't have a model number or anything to ID it with yet, but I should presumably be able to get 12vdc/2a from that. Just not sure how a PoE switch works yet.

6

Mouser carries Recom DC-DC switching converters. Once you get a handle on the voltage level coming in, maybe you can find a converter or two that will meet your needs.

7

Is that 30W an input rating? Or the total power sent out over multiple lines?

8

If you don't need the full 2 amps output all of the time (say for example you will be running a motor for a couple of minutes and then it will be idle for a while) you can add some sort of energy storage device like a battery or big capacitor that your lower input power can charge during idle time but which can supply the load when needed.