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Sorry if this is a stupid question, I'm a newbie just getting into the actual hardware side of things.

Obviously I'm starting small, just a simple re-balling of a BGA chip to build my own Single Board Computer and wanted to know how to do all of that. Anyway, I'm wondering if it's possible to put two NAND flash memory chips onto the same circuit to double the memory (i.e. 8GB chip + 8GB chip = 16GB chip). Tried Google, but it's bloated with millions of useless blogs that bury any useful information.

Something like this (except obviously all connections are connected): Schematic to clarify

If not, what would theoretically happen? My guess is it would write the same data to both chips (which may prove useful), but I really don't know.

Thanks in advance :)

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  • \$\begingroup\$ You might want to familiarize yourself with the term(s) chip select/enable \$\endgroup\$ – PlasmaHH Jun 3 '16 at 14:07
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    \$\begingroup\$ Interestingly, the parts you reference above are stacked already. spansion.com/Support/Datasheets/S34ML08G1.pdf \$\endgroup\$ – Peter Smith Jun 3 '16 at 14:11
  • \$\begingroup\$ Huh, didn't notice that. Will that affect its' ability to be 'stacked' again or can these types of complexities go on indefinitely? \$\endgroup\$ – Noah Wood Jun 3 '16 at 14:16
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    \$\begingroup\$ The term "Stacked NAND" also refers to putting multiple dies (chips) in one package. To adress the individual chips, as mentioned, Chip Select or Chip Enable signals are used. Why this stacked RAM ? Because then you can fit more memory in the space of a single package. \$\endgroup\$ – Bimpelrekkie Jun 3 '16 at 14:26
  • \$\begingroup\$ You can keep parallelizing chips until (a) the bus characteristics deteriorate because the load is too heavy or the bus too long or (b) you run out of driving pins for chip enable signals. \$\endgroup\$ – pjc50 Jun 3 '16 at 14:35
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That's what the "chip enable" (CEn) signals are for.

These are active-low (that's what the trailing n means, may also be rendered as a bar over the name in diagrams). You wire all the pins of two chips together except the chip enables, and then wire the CE signals to an address decoder of some sort.

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