WIZnet Developer Forum

W5500 Crystal selection

Hi,

I have read numerous forums and conversations about the correct crystal selection for W5500 and I see lots of people had stability issues which makes me worried. Obviously the datasheet has mentioned some specific characteristics for the crystal: 25MHz, 30ppm Frequency tolerance, 18pF load capacitance. I have four questions:

1- What’s the ESR value I should aim for this crystal?

2- Is HC-49/US package preferred or 4-SMD?

3- Does this look like a good option: (FY2500016)
https://www.mouser.com/ProductDetail/Diodes-Incorporated/FY2500016?qs=ZrPdAQfJ6DPs%2BuUDAtNVtA%3D%3D
If not what part number have you actually used in production and it worked perfectly?

4- For the load capacitance, is it a good practice to follow design reference from Wiznet which suggests 18pF capacitors. I understand following formula and assuming 5pF Cstray on the paper gives us 26pF not Wiznet’s suggestion of18pF.

Thank you,

Any insight would be appreciated. Please advise.

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