I'm planning on buiding my own LED lights for a new garage space, ones that utilize PoE and are controlled by PoE powered light switches that I also plan to build. I've identified two chips that I can use to handle the PoE handshake (Maxim's MAX5995B and ON Semiconductor's NCP1095). I could use a shield but they don't support the 60-90w capacity of the 802.3bt standard. My problem is that building this kind of circuit board is way beyond my current abilities. The board would have to step-down the voltage to 12v or 24v and then step that down to 5v or 3.3v to power the Arduino. Has anyone ever attempted this?
I'm curious as to why you have chosen to use PoE, I can't think how that would be an advantage.
The board would have to step-down the voltage to 12v or 24v and then step that down to 5v or 3.3v to power the Arduino.
I don't know if this will help you but when I wanted to go from 50V to 12V I wondered if a standard mains powered wall wart would work on 50V, so I tried one and it worked perfectly well. You may well find you can get one with a 5V output to work from the 50V to 60Vish of 802.3bt type 4.
A 60W switchmode power supply is pretty advanced, even if the negotiation part is handled by a smart chip. How about a module like https://silvertel.com/ag5810/ ?
PerryBebbington:
I’m curious as to why you have chosen to use PoE, I can’t think how that would be an advantage.
I’m building a large detached garage and addition to my house and want to have maximum flexibility in the lighting and eliminate the need to run line voltage everywhere. Line voltage will be run only to the outlets and some junction boxes, but all wall switches and lights will be low voltage. This is still a work-in-progress, but am thinking of using cheap android PoE tablets for “wall switches”.
OK, thank you. I've no further suggestions, sorry.