This board splits a PoE+ input into a 24V 85W output and a USB interface for data. It is meant to be used as part of my home media system for driving in-wall speakers.
- Uses a Silvertel Ag5800 for PoE control and DC-DC conversion
- From PoE+ to PoE++ (Type 2 to Type 4, 802.3at and 802.3bt)
- Outputs up to 85W of power over 24V
- Converts the data from 4 pairs Ethernet to USB 2.0 with a Microchip 7850
- 10/100/1000 Ethernet (but limited by USB 2.0 speed at around 400 Mbps)
My usage of this board is with a HiFiBerry Amp2 and a Raspberry Pi Zero 2 W.
Power is provided to the Amp2, which in turns powers the RPi and drives 2 speakers.
Data is provided to the RPi via Micro USB 2.0. The data output of the media_poe_splitter is done over a flex ribbon
cable (pitch 0.5mm, 6pos) to fit dimension constraints. The associated usb_breakout board transforms that into a Micro
USB connector that can be plugged in the RPi data port.
Thermal management should be done accordingly to the recommendations provided by the Ag5800 documentation.
The board has 4 heat pads which should be coated using thermally conductive oxime board mounting the Ag5800.
- Ag5800
- https://silvertel.com/images/datasheets/Ag5800-datasheet-%20IEEE802_3bt-Power-over-Ethernet-4-pair-PD.pdf
- The EVALAg5800 schematic and BOMs are not publicly published by Silvertel, but they sent it over by email when asked for it. As such, I won't reproduce them here, but here are some public references for similar boards:
- LAN7850
- Wurth Elektronik PoE Ethernet to USB board