Hi Eugeny,
Here’s a picture of the board near the clock and W5500.
The C25 capacitor fell off earlier, but obviously during tests it was present: I guess the crystal is not as close to the W5500 as it could be, and the XI and XO track lengths are different, but I’d be surprised if that’s what’s causing this.
You might remember this thread - that was the previous design. I suspected the RJ45 transformer was to blame so I made a new version with a different (recommended) part - but I got the same issue which is why I now suspect the clock.
The schematic is the same as shown in post 2 in that thread, except the transformer is now a Cetus J1B1211CCD (also recommended by Wiznet) with appropriately updated routing (it has separate central taps for RX and TX).
Cheers!
