I am looking into some fried microsd cards that I’ve seen from BeagleBone Blacks. I’m not sure what is causing the problem yet, but while reviewing the BeagleBone Black schematic I noticed that the VDD_3V3B regulator looks like it might have swapped input and output capacitors. According to the manual for the regulator, http://www.ti.com/lit/ds/symlink/tl5209.pdf, the minimum output capacitance should be 2.2uf, but the schematic shows a .1uf capacitor for the output capacitor, C20. Just wondering if that was on purpose. I don’t think this is the cause of the fried sd cards I’m seeing because there’s plenty of capacitance at the microsd port, but it looked odd to me.
There is plenty of capacitance on the output of that regulator found in other locations on the schematic…
That will not fry a 3.3V SD card.
Gerald