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What about BGA?

BGA is not the best package ever for hobbyest.Small pads under the chip make really hard to work with it.But if you  get challenged this can be interesting adventure.
Here is the situation, I get a Nexus 7 (2013) main board in my hands. Sadly the eMMC was corrupted and of course not work. This is why I'm holding in my hands :D
Looking the eMMC specs it is an SDCARD with 8bit bus, same protocol for communication, nothing too complicated and luckily exist something called 1bit mode.
In this mode the chip is using only 1 bit to transfering data.So you need to breaking out only 6 pins.

  • 2 type of power
  • ground of course
  • CMD pin for command or data flag
  • Clock for synchronous operation
  • Data0 for transferring data


My eMMC is type 4.5 so I can use 3.3V for logic levels.Be carefull! eMMC 5 and up support only 1.8V logic levels.
Turn on your iron and let it flow!
Wires soldered on the eMMC

uSD card reader and eMMC are connected
After soldering and gluing everything thougeather you can connect the cardreader to a linux box and you can mount the all partitions if it has a valid common file system. I succesfully make a backup of the whole eMCC, but and here is the problem , I can't write any data to it.When I try to write something, it is immedietly disconnecting from my computer, maybe a power/coupling issue or the eMMc itself.
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