W5500 not drawing power

Question

Hi, I’ve assembled a new prototype board with the W5500 and it appears to never power up. I’ve double checked all the connections and I get 3.3v power where I expect it right up to the decoupling caps and after that nothing, and nothing on the 1.2v rail. Ethernet cable and switch port is confirmed good, with auto-neg enabled, but the link light on the switch never illuminates. The LC of my crystal is 18pF so allowing for 5pF Cstray, the crystal caps seem reasonable. Sadly I don’t own a oscilloscope that will measure up to 25Mhz to 100% confirm this. The schematic was based on the reference design & Adafruit’s Ethernet FeatherWing. I’ve attached a screenshot of that part of the board layout and schematic. C19 I get a clean 3.3V after that nothing. Could this be a bad chip or is there something else I can check through first? Any thoughts are much appreciated. Screenshot 2024-05-02 at 15.01.061943×730 15.1 KB Screenshot 2024-05-02 at 14.40.131141×1257 182 KB

Eugeny · Answer

Mistake in connecting RX. What state reset signal is in? And how did you assembled, and at which temperature?

nstansbury · Answer

Hi, what are you seeing about the RXn connections? Reset is pulled up to 3.3v at power on. Board was reflowed in a reflow oven and hit the correct solder profile through out. I’m getting continuity on expected circuits.