SD card desgin guide lines

[marcohaddad]

Hello,

I'm having some difficulty to find out why my uSD card works fine on a FRDM-K64 but does not on my new board with K24.

I have been searching for design guides related to the Kinetis SDHC interface, but didn't find any.

Any information on good practices for SD card PCB design would be appreciated.

Thanks.

[jeremyzhou]

Hi Marco,

I've attached the PCB files of the FRDM-K64F.

However I'd like to suggest that you should dig deeper and figure out the root cause of issue, as you know, the software code also can raise the kind of the issue.
Have a great day,
Ping

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[marcohaddad]

Hello, jeremyzhou,

Thanks for your answer. But I already had that.

When I checked the FRDM-K64 pcb layout I noticed that it looked like no special care were taken except some ground guard lines around the clock line, where was possible, and the intent to keep the other lines to the same length among them.

The error I get with two 4GB uSD of different makers is also different: the first one fails on card detection and the other fails a bit ahead, at file system initialization. Both work fine on the FRDM-K64 tough...

Best regards,