Hi /diy/ this is my first post here, I've been lurking around.
Anyone can help me out with this mini-project? I want to make a USB charger using RJ45 and my spare USB cable.
Check this out: http://www.youtube.com/watch?v=7iSC9yXxVVc&t=3m50s
>>1005555
>OP here
I only have the following:
so to make things clear, you want to charge something that has a usb port using an ethernet connection?
that wont work unless you are using an ethernet device that supports poe
>https://en.wikipedia.org/wiki/Power_over_Ethernet
and even then you would need to reduce the voltage from 45~50 down to 5 (its not that hard but it requires some passive components)
>>1005559
Yep that's what I want to try, Now that is something that I haven't considered and thought it would be okay to just simply jump in and do a connection. If you can help me / provide me a link which has some more additional details about it, that would be perfect mate! :)
>>
well, if you read on that power of ethernet wiki page you will see that you need to step down the ethernet voltage to 5v (usb voltage). you could build something youself using a linear regulator like the lm7805, but since you still need pointers on this i would recomend getting a step down buck converter from fleabay
>http://www.ebay.com/itm/DC-DC-buck-Converter-step-down-power-Module-8-50V-12V-24V-36V-to-5V-USB-OUTPUT-/221507312505
already has the usb output and all
(poe supplies at least 12w of power so you would get close to a 2 amps usb charger)
next you need to figure out what wires on the ethernet connection carry the power, so you can connect the input of the step-down buck converter to it, that wiki page also has a pinout list so use that
>https://en.wikipedia.org/wiki/Power_over_Ethernet#Pinouts
then you need to get a ethernet device that can supply power to the ethernet connections, browse your local electronics shop or ebay for one (a switch or a router with PoE is enough)
and thats about it
gl