Running Jetson Nano without direct power supply (using PoE)

Autonomous Machines Jetson & Embedded Systems Jetson Nano
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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%.)

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.

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!

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Many thanks for your kindly sharing to community, appreciate!

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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.

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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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