POESP-board 1.0
Overview
The POESP, for PoE-ESP, is a ESP32 breakout board with LAN and PoE. Please understand well this device is NOT insulated from the PoE, so use only in suitably insulated setups. There is an usb interface for loading the firmware and debugging, be aware the ground of this interface might be at +48V from PE (or worse) as well ! So use a well-insulated laptop and/or do not use when powered by PoE. Stepdown from 48V POE to 3v3 is done in two steps, the intermediate voltage can be set at any voltage between 5 and 24V.
This design and fromfactor is abandoned by me, there might be an improved 2.0 in the future (but please do not hold your breath .. :-)
There were about 10 prototypes assembeled. There are no PCB's available, but the pastastencil is @ Makerspace Leiden.
Main components:
- ESP WROOM 32 module
- LAN8720 ethernet phy
- JD0-0004NL-X1 ethernet jack with built-in magnetics
- TPS2375 POE controller
- LMR16010 primary stepdown, 48V POE -> 5 - 24V @ 1A
- MCP16301 secondary stepdown, 5-24V -> 3v3 @ 600 mA
Default SMD size is 0603.
Sources of information
About connecting the ethernet phy to the ESP.
- https://sautter.com/blog/ethernet-on-esp32-using-lan8720/
- https://www.waveshare.com/w/upload/0/08/LAN8720-ETH-Board-Schematic.pdf (note: not very accurate. Check config in the LAN8720 datasheet)
- https://en.wikipedia.org/wiki/Media-independent_interface#Reduced_media-independent_interface Interface between ESP and eth phy.
Suppliers
- Boards & stencil: Elecrow
- ESP32: AliExpress
- Rest: Mouser
