Hackaday Links: February 20, 2022

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Sounds like somebody had a really bad day at work, as Western Digital reports that “factory contamination” caused a batch of flash memory chips to be spoiled. How much, you ask? Oh, only about 7 billion gigabytes! For those of you fond of SI prefixes, that’s 7 exabytes of storage; to put that into perspective, it’s seven times what Google used for Gmail storage in 2012, and enough to store approximately 1.69 trillion copies of Project Gutenberg’s ASCII King James Version Bible. Very few details were available other than the unspecified contamination of two factories, but this stands poised to cause problems with everything from flash drives to phones to SSDs, and will probably only worsen the ongoing chip shortage. And while we hate to be cynical, it’ll probably be prudent to watch out for any “too good to be true” deals on memory that pop up on eBay and Ali in the coming months.

Speaking of broken stuff, we came across a site called FailScout, which purports to be “a crowdsourced database of broken and worn-out products.” The idea apparently is to document cases of what appears to be either systematic manufacturing defects, engineering problems, or outright planned obsolescence. The goal of this is ostensibly to hold manufacturers accountable for their products, but we can see how this could just devolve into a morass of ax-grinding by people who have unreasonable expectations about how long products should last. Yes, pretty much everything we buy is subject to “value engineering” decisions in terms of materials and designs, and some of that will no doubt send products to the landfill long before their time. But when someone is complaining about broken five-year-old flip-flops, we think we’ll take a hard pass on this one.

For the numerically obsessive among us, a momentous day is approaching. This coming Tuesday will be “Twos Day,” when everyone’s calendar will show 2/22/22 (or 22/2/22, if you’re so inclined) all day. And for a special treat, if you want to add to the symmetry and don’t mind getting up early, or staying up late, you can watch the clock flip to 2:22:22 on the appointed day. If this excites you as much as watching an odometer flip over, you’ll probably want to visit this interesting Palindrome Date calculator, and see how long it’ll be before some other interesting sequence of numbers will be encoded in the date.

While trolling through Hackaday.io the other day, we happened upon a project that looks interesting: a miniature selective soldering machine. Until we saw this, we hadn’t even wondered how mixed through-hole and SMD boards are assembled; selective soldering seems to be the answer. It seems to be a very localized version of wave soldering. Instead of using a large tank that covers the entire underside of a board, the molten solder is pumped into a special nozzle to form a tiny fountain. This little solder volcano is moved around the board to all the through-hole leads that need soldering, and it’s a very satisfying process to watch.

And finally, because the world is crying out for a car with 80’s styling and a 21st-century electric drivetrain, it looks like DeLorean is trying to make another go of it. Maybe it’s the nostalgia of the approaching 40th anniversary of the first installment of the Back to the Future trilogy, or maybe it’s just because they can, but whatever the reason, the hype machine is already rolling, albeit with nothing but a silhouette shot of the iconic and never-practical gullwing doors opening. And even though it’s electric, we wouldn’t count on a 1.21-gigawatt battery. Or a Mr. Fusion.

23 thoughts on “Hackaday Links: February 20, 2022

    1. It sounds like the contamination was in BiCS 3D NAND flash (apparently 96-layer QLC tech), which is a newish high-density format. Apparently a single BiCS die holds 1.33Tb (166GB), so 6.5 billion gigabytes is about 40 million BiCS flash chips.

      I’m not what package WD/Kioxia use, but Micron seems to use 132-VBGA and 272-VBGA for NAND with similar capacities. These are 12x18x1.0mm and 14x18x1.3mm, respectively, giving volumes per chip of 0.22mL and 0.33mL.
      That gives about 13,000 liters of 132-VBGA chips or 8,400 liters of 272-VBGA chips.

      An Olympic swimming pool holds 2.5 million liters, so 132-VBGA chips fill 5.1% of the pool, and 272-VBGA chips fill 3.4% of it.

      That’s not very relatable, though. It looks like a kiddie pool maxes out around 250 gallons (950 liters), so 6.5EB of flash takes up at most 14 kiddie pools of 132-VBGA chips or 9.0 kiddie pools of 272-VBGA chips.
      Alternatively, Wikipedia says a concrete mixer truck most commonly holds 10 cubic yards (7.6 cubic meters) of concrete, which is 7,600 liters. That’s 1.7 concrete trucks of 132-VBGA chips or 1.1 concrete trucks of 272-VBGA chips.

      However, one of the big features with BiCS is die-stacking, which allows you to have up to 16 dies in the same flash IC. That would make the total volume of flash lost less than one kiddie pool for either packaging.

      (All numbers have been rounded to two significant figures)

  1. The DeLorean article is behind a paywall. (Personal info is currency too now).

    I was optimistic about the FailScout site. We really do need a way to call out manufacturers that clearly deliberately build in obsolescence or paywall features without being honest about them in the first place or building in internet / server dependence then switching of the server to brick the device.

    I though NAND FLASH was used for specifically “fast” applications like SSD’s. Is that what’s in our crumby USB FLASH stick to? And is that what is effected. It’s not clear to me. Any help appreciated.

    1. I think the real difference between USB flash drives and SSDs is the number of chips. SSDs have a bunch of flash chips being accessed in parallel, which ups the overall read & write rates, while most thumb drives have just one chip.

  2. Bwaaa ha!
    > someone is complaining about broken five-year-old flip-flops
    I was wondering who was using flip-flops in this day and age (D? T? JK?), how they were packaged, and why they were burning out…

  3. WD’s flash chips are provided by Kioxia ( https://about.kioxia.com/en-jp/news/2022/20220210-1.html “contamination of the material used in its manufacturing processes” )
    So my guess would be that radioactive isotopes made it into the supply chain, or more precisely there was a failure in the supply chain for the isotopically enriched silicon (single crystal 99.9999% pure silicon-28) which may be required for latest generation of cutting edge devices.

  4. I was disappointed after clicking the ‘Broken 5 year old flip-flops’ link. I was expecting an article about bad 74LS74s (or similar). Instead it was about what us Aussies call ‘thongs’!

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