Running Jetson Nano without direct power supply (using PoE)

I’ve been looking for components to run a Jetson Nano straight off of PoE, without a separate power supply.

The reason this can work, is that the Jetson has a pin header that breaks out the power-over-ethernet it may receive from the Ethernet port. You can then wire a DC DC converter to this PoE (which typically is 24V or 48V if you have PoE from your switch) and make it generate the 5V/10W or whatever that the Jetson wants (depending on your power mode and utilization.)

This product is $11.50 in single quantities, and tolerates all PoE voltages up to 53 Volts (which is 48 Volts plus 10%.)
https://www.digikey.com/product-detail/en/mean-well-usa-inc/NID35-5/1866-NID35-5-ND/10659863
It will, according to specifications, generate any power needed up to 3.5 Amps, which should be a Jetson running full tilt with a fan and some moderate power draw on the USB port.

If you know for sure that your PoE is 24V, or a very well regulated 48V that’s less than 50V, you could use a Pololu D36V50F5 buck converter:


(This product costs $20, and is made in the US, which may matter to certain government manufacturers, and people who prefer in-country support over the cheaper price from offshore components.)

You also need a simple diode bridge, because PoE doesn’t guarantee polarity, depending on wiring standard and cables used.
https://www.digikey.com/product-detail/en/smc-diode-solutions/DB155TB/1655-1827-ND/7244855

The wiring is pretty simple: Jetson motherboard header J38 -> diode bridge -> DC DC converter -> 5V and GND pins on the Jetson GPIO header J41.
Because you power it through the GPIO header, you don’t need to worry about the USB-versus-power-connector selector.

Hopefully this helps someone!

Many thanks for your kindly sharing to community, appreciate!

But most likely will not is because standard PoE needs a basic handshake before the PSE device enables power to the PD device. Therefore you will need a minimal PoE interface besides the bridge and the DC/DC converter, which starts amounting to a more complex circuit.

I found your post because I was looking into a simple solution like you describe. So, that said, have you tried this with any success?

Kind regards.

No, this only works for “passive PoE.”
Which isn’t af compliant, but is cheap and thus available from the usual low-cost sources.

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