We have designed a product using the MP257, and based the board layout of the EVK and we are now taking the combined product through RED & FCC testing.
Generally the board is very quiet, but we are experiencing problems with the Ethernet clocks and we are seeing strong 125MHz & harmonics emissions.
We are using the RTL8211F and haven't changed the traces associated with the EVK, we loaded the design into Altium, and made a few changes.
My question is about Clock sources, what is the best way to run the 125MHz, by default CubeMX seems to generate clock, and the RTL8211 also seems to generate a clock, is this correct?
I can see 4 125Mhz on the spectrum analyser, 3 very close together, I believe from the RTL8211 crystal and 1 approx 40 KHz apart which I assume is from the MP257, does this seem to make sense?
The switch functionality is working
