No ethernet connectivity with ESP-32-WROOM through PHY transceiver - Page 1
Forum section: electronics / beginners

author: padagra
author_rank: Contributor
timestamp: October 04, 2019, 03:12:36 am
content: Hello all, I moved this post from Microcontrollers to here since it seemed more fitting. I’ve been racking my brain trying to figure out what I’m doing wrong, maybe one of you will see something I’m missing.So I designed a board based off the Olimex ESP-32-POE for easy sensors in home automation. The Olimex board starts to add up cost with a lot of individual units, I found it was cheaper for me to design the version I need stripped down from their design. I’m going to apologize in advance for my schematics, like I said I’m new and still learning please go easy on me. This is the first PCB design I’ve done, it was supposed to be straight forward since I have an open source design I could copy directly from.Currently I have working:- POE 5v regulator- 5v to 3.3v regulator- Programming Header- IO Breakout- Addressable LEDsThe only part that is not working is the ethernet PHY chip. I’m using the same exact code provided from Olimex using the same components. I’m thinking it must have something to do with my PCB design, I can’t see any differences in the schematics.This last board I received was drawing 1.43amps when I had the ethernet transistor enabled by the Esp-32 microcontroller. Turns out I had a ground via shorting out a trace which was found using a thermal camera. Once I broke the trace on the circuit board, the short went away but I still cannot get ethernet connectivity as expected.Troubleshooting notes:- I also have an Olimex board in hand and have been running my code against it as a baseline, everything works fine on the Olimex board.- I have checked to make sure the select lines through the resistor networks are selecting the appropriate PHY mode on the chip (2.2k ohm resistors)- I am using a different style of rectifying POE jack than the Olimex design has but I breadboarded an “interface” to remap the pins and tested this jack on the olimex board with successThe pictures in the post show the most recent ordered revision with the grounded trace however it was only one filter? capacitor lost for the power rail on the ethernet PHY chip.More notes:- Using low temp lead free solder paste- Hand placed components- Reflowed using T962 (modified) oven- All components reviewed under microscope and any issues repaired using rework station- I’ve been powering up the board using the programming header so 3.3v only. This shouldn’t be a problem considering the only 5v uses are external devices through the IO port which is not in use at the moment. The POE does work when plugging in an ethernet cable with POE on.Links:Olimex Board:https://www.olimex.com/Products/IoT/ESP32/ESP32-POE/open-source-hardwareOlimex Schematics:https://github.com/OLIMEX/ESP32-POE/raw/master/HARDWARE/ESP32-PoE-hardware-revision-C/ESP32-PoE_Rev_C_Color.pdfMy gerber files:https://drive.google.com/open?id=1gMgqzTtAZ7wnyaUZ_DDinuoLpiHPCpMyMy schematics:https://drive.google.com/open?id=1OJd6zbYkBCBy7uq8c__bVKlTIwECfEKWThank you in advance for the help, I have a feeling this is going to be a simple issue I am just looking past.Adam