While we don't usually cover SD cards, SanDisk's announcement of 512GB Extreme PRO SD card caught my eye today. There are currently only a couple of 256GB SD cards available and most OEMs have not been able to go above 128GB, so the Extreme PRO is the highest capacity SD card in the world, which really speaks for SanDisk's NAND and packaging expertise. 

SanDisk Extreme PRO SDXC UHS-I Memory Card Specifications
Capacities 128GB, 256GB & 512GB
Read Speed Up to 95MB/s
Write Speed Up to 90MB/s
Warranty Lifetime Limited

The Extreme PRO comes in SDXC format and utilizes UHS-I interface, which is good for up to 104MB/s. As you can see in the table above, the Extreme PRO comes very close to saturating the interface and it carries UHS Speed Class 3 rating, meaning that it is suitable for capturing 4K video. The largest market for the new Extreme PRO SD cards is obviously video professionals because as we transition to 4K video, the need for storage increases substantially, which in turn opens market for larger SD cards.

While SanDisk didn't release any details of the internals, it's pretty safe to assume that the 512GB Extreme PRO consists of 32 x 128Gbit (16GB) dies. The photo above is from SanDisk's 2014 Investor Day presentation where the company claimed that it has the technology for a 32-die SDXC card and with the Extreme PRO the technology has made it into the retail. Since SanDisk/Toshiba doesn't have a 256Gbit NAND die (nobody has one in mass production yet), the only way to achieve 512GB is through a 32-die stack. SanDisk hasn't specified whether the NAND is MLC or TLC, but given that it is a high-end product I'm guessing it is MLC based. 

EDIT: As some of you mentioned in the comments, it seems to be two 16-die stacks instead of a single 32-die stack. SD cards definitely have the room for two die stacks and the photo also shows two 16-die stacks instead of a single 32-die stack. Either way it is impressive since nothing else comes close to the capacity SanDisk offers.

All capacities are available now and the MSRP for the 512GB model is $800, which is certainly high since 512GB SSDs retail for close to $200. However, the Extreme PRO is the only SD card that is available in such a high capacity, so I would say the premium is justified. Stacking more dies on top of each other will always have a negative impact on yield as the wires have to be longer and there are more wires to connect, so the room for errors increases and thus the manufacturing cost goes up as well. 

Comments Locked


View All Comments

  • pixelstuff - Thursday, September 11, 2014 - link

    I think the Panasonic GH4 actually requires a card with the UHS-I Class 3 speed rating when recording in 4K at 100Mbps or Full HD at 100 or 200 Mbps.

    However, it also helps when getting data back off the card too even for low bit rate recordings by other cameras.
  • Mayuyu - Thursday, September 11, 2014 - link

    So this is literally worth it's weight in gold.
  • mkozakewich - Friday, September 12, 2014 - link

    It seems they weigh 0.07 oz, in general. That much gold would be about $90, at most.

    I have no idea how much diamonds cost, though! Googling reveals $800 per carat, and a carat is 0.007 oz, so Diamonds are worth ten times as much as this SD card by weight.

    Further Googling shows that the lowest-grade 10-carat diamond would cost almost $170,000. I think being 10 carats makes them extremely rare and more valuable.
  • SuperSpy00bob - Friday, September 12, 2014 - link

  • Samwise Clemens - Wednesday, September 17, 2014 - link

    ahem... https://what-if.xkcd.com/31/
  • semo - Friday, September 12, 2014 - link

    This is why smartphones need to ditch microSD slots and go back to full size SD. Phones are no longer getting like they used to years ago. All these 5"+ devices have plenty of space for dual SIM, full size SD slot, user replaceable batteries and Qi charging.
  • althaz - Friday, September 12, 2014 - link

    No, they REALLY don't.
  • semo - Friday, September 12, 2014 - link

    I'm guessing you are not interested in shooting long HD videos with your smartphone. It's not for everyone but there's plenty of people that will appreciate a full size SD slots. For the rest, there's plenty of phones without external storage whatsoever
  • hojnikb - Friday, September 12, 2014 - link

    Hmm. Something has come to my mind. Since sd cards are big enough to hold two packages, isn't it kinda pointless to go with 32 die stackes ?

    I mean 512GB is totally doable with 2x 256 packages, each having 16 128Gbit dies. Or am i missing something here ?
  • hojnikb - Friday, September 12, 2014 - link

    Or does 32 die stack just means that there are 32 dies in the sdcard but NOT stacked on to each other in a single package ?

Log in

Don't have an account? Sign up now