[HN Gopher] SanDisk Extreme Pro failures result from design flaw...
___________________________________________________________________
 
SanDisk Extreme Pro failures result from design flaw, says
researcher
 
Author : dangle1
Score  : 134 points
Date   : 2023-11-12 16:27 UTC (6 hours ago)
 
web link (www.tomshardware.com)
w3m dump (www.tomshardware.com)
 
| jiripospisil wrote:
| Sounds like Western Digital's strategy is to play dead and wait
| for it to blow over. And it will most likely work.
 
  | baz00 wrote:
  | They saw Apple get away with it and tried to do the same.
 
    | RCitronsBroker wrote:
    | no matter how bad the idea, there's always someone waiting to
    | turn Apple's bad idea into a poorly implemented, even worse
    | idea
 
    | bboygravity wrote:
    | I've had a Fujitsu (if I remember correctly) drive many many
    | years ago that had a hardware bug that would cause an IC on
    | it to spontaneously flash fire and die.
    | 
    | It was a known flaw. They got away with it too.
 
  | ipqk wrote:
  | There will probably be a class action lawsuit where everyone
  | that bought one gets a $20 coupon towards a new WD product, and
  | the lawyers make millions.
 
| wkat4242 wrote:
| Looks like this particular problem is easy to fix though.
 
  | Zetobal wrote:
  | By whom? Your granny who just lost all the pictures of their
  | grandchildren?
 
    | wkat4242 wrote:
    | No but by me or anyone else who can hold a soldering iron :)
    | 
    | It's much much easier than a BGA cracking issue, or something
    | internal in the flash which is basically unfixable. This is
    | just some components tombstoning. It shouldn't cost a lot to
    | get it fixed (of course Sandisk should take care of that)
 
      | croes wrote:
      | Guess who gets blamed if your soldered SSD fails.
 
        | lambdasquirrel wrote:
        | Yeah, this stuff is harder than it looks. If you need too
        | much time with the soldering iron, the temperature can
        | conduct through the wire and fry other components, those
        | sensitive ICs that are the flash chips in particular.
 
      | mike256 wrote:
      | Are you sure the BGA is soldered correctly? Regarding the
      | soldering, almost every 2nd component looks pretty bad.
 
      | kmbfjr wrote:
      | By anyone who can operate a stereo microscope and a surface
      | mount solder station.
      | 
      | A Fisher-Price "My First 40 Watt Weller Soldering Pencil"
      | won't cut it for this type of repair as you're not just
      | flicking diodes off a board to "unlock" something.
 
        | wkat4242 wrote:
        | It does for me.. I've soldered 0805 (and 1206 which was
        | most of them fortunately) components with a screwdriver-
        | tipped aldi iron as I didn't have anything else
        | available. It was not a great experience but being very
        | careful with the corner of it it worked.
        | 
        | But this is a super capacitor so it'll be a lot biger
        | than that.
        | 
        | But a hot air rework station or a really fine
        | temperature-controlled tip is way better of course, which
        | is what I usually use.
 
      | dboreham wrote:
      | The article unfortunately was written by someone with no
      | clue so we don't know why tombstoned components (shown in
      | the picture) were not caught in inspection/test. They imply
      | the failures happened in the field, but that's not where
      | tombstoning happens. Presumably what happened was that the
      | supercap (looking like [1]) tombstoned in reflow. Then
      | circuit test failed to test that it was installed so the
      | unit was shipped. Subsequently in the field the unit
      | suffered a sudden power loss with pending writes. Normally
      | the supercap provides power for long enough to flush
      | pending writes to NAND. But since it was open circuit, the
      | power fail flush never finished, resulting in corrupted
      | storage. Fixing the open circuit solder joint as you
      | suggest does not remedy the problem for the user because
      | their data is still gone.
      | 
      | [1] https://www.digikey.com/en/products/detail/seiko-
      | instruments...
 
        | wkat4242 wrote:
        | > but that's not where tombstoning happens
        | 
        | yeah I know, unless the board gets so hot it unsolders
        | itself, which is very very doubtful (and definitely a
        | fault of its own).
        | 
        | I thought it was more of a stability problem though.
        | Nothing a good backup should cover, and the device should
        | be fine after soldering the component.
 
        | nurple wrote:
        | One capacitor on a tank array would definitely reduce its
        | total capacitance, but they are nearly always in parallel
        | and would not cause a failure of the whole tank, and the
        | device would be inoperative if the output of the array
        | was shorted.
        | 
        | I'm skeptical that losing one capacitor in the array
        | would cause the failure mode you're describing.
        | Especially if the age of the devices is considered, the
        | array would have been designed with margin to withstand
        | capacitance loss as the device ages.
 
        | wkat4242 wrote:
        | Perhaps tombstoning causes it to short the whole array? I
        | could see that happening if it's positioned just wrong.
 
        | lightedman wrote:
        | "I'm skeptical that losing one capacitor in the array
        | would cause the failure mode you're describing."
        | 
        | Depends on what the capacitor is being used for in the
        | circuit. In many cases, having a cap fail open results in
        | a higher current draw which kills the unit if left in
        | operation for too long. This is the case on some of the
        | off-road lighting I manufacture. If one cap is present
        | and fails open at ground, the circuit overloads. If the
        | cap is connected to ground but not the rest of the
        | circuit, the circuit doesn't operate.
        | 
        | Regardless, one component being off can cause a whole
        | chain of maladies.
 
      | yjftsjthsd-h wrote:
      | If a fix requires soldering, then to >95% of people it
      | doesn't exist. I would be surprised if even most computer
      | repair ships were up to it.
 
| lukevp wrote:
| We have one of these as part of a critical video workflow.
| Anything we can do to mitigate it? Or do we just hope it's not
| impacted / replace it soon?
 
  | ohyes wrote:
  | Replace it with a different SSD sounds like the only option.
 
  | gjsman-1000 wrote:
  | RAID and a backup strategy? There should not be a single point
  | of failure. Just getting 2 new SSDs with a RAID 1 would be a
  | massive improvement.
  | 
  | And, of course, a separate backup for them because RAID is not
  | a backup.
 
  | FirmwareBurner wrote:
  | If it's a critical workflow on which your business rests, then
  | you immediately replace it with a better model/brand as that's
  | a business tax write-off. Plus you have the usual on-site and
  | off-sie back-ups which you should already have for your
  | business.
  | 
  | You do have a back-up set up that you also test, right? Right?
  | 
 
    | VHRanger wrote:
    | If it's a video workflow it's likely more of a working drive,
    | backups don't always keep up with the changes on the drive
    | fast enough.
    | 
    | Unless it's part of a RAID array or something, but by that
    | point you'd shell the money out for a better drive
 
  | rwmj wrote:
  | The fact you have one SSD in a critical workflow is an
  | immediate red flag. You should have some kind of redundant
  | solution with backups even if you didn't suspect particular
  | SSDs are prone to failure.
 
    | lazide wrote:
    | 99% of small businesses just flat out 'nope' out when it
    | comes to proper backups or redundancies though.
 
  | jpk2f2 wrote:
  | Replace it immediately, not soon.
 
  | ikekkdcjkfke wrote:
  | I think one can enclose m2 ssd's in usb adapters, then you just
  | use well proven tech like samsung 970 pro, been chugging along
  | on our build server for years now
 
    | mgerdts wrote:
    | Many of these adapters have their own quality problems which
    | vary with the version of the controller. That version number
    | is rarely available prior to purchase.
 
      | asmor wrote:
      | If you have a critical application, you can afford a vendor
      | that uses TB4 with a good reputation.
      | 
      | Here are some options:
      | 
      | https://www.owc.com/solutions/thunderbay-flex-8
      | 
      | https://www.startech.com/en-us/hdd/m2e4btb3
 
  | mpol wrote:
  | If it's critical, you should not use a cheap SSD. It is better
  | to use a SSD for professional use, for servers.
  | 
  | I have seen and heard too many consumer market a-brand SSDs
  | break.
 
    | asmor wrote:
    | The Extreme Pro lineup isn't even considered a "cheap SSD",
    | it's their highest end offering before you dip into their
    | G-DRIVE line of rugged SSDs.
 
  | shocks wrote:
  | It would probably help to describe your workflow so we can
  | offer specific suggestions.
 
| spandextwins wrote:
| 3 copies. Always. Spread them out on different companies and
| technologies.
 
  | iancmceachern wrote:
  | And physical locations
 
| RDaneel0livaw wrote:
| I'm astonished that after WD bought the SanDisk brand they kept
| it alive. You couldn't pay ME to use anything under that name,
| it's so negative. Maybe now with this critical failure they'll
| just slowly start branding things with any of the other myriad of
| brand names they've bought "hgst" for instance and slowly kill
| the brand.
 
  | tentacleuno wrote:
  | What's wrong with SanDisk? Out of the loop here -- I had a
  | SanDisk SSD around 5 years ago and it was absolutely great;
  | it's still going today (it's seen quite a bit of use, too.)
 
    | amatecha wrote:
    | Yeah, kinda no clue what the controversy is cuz I've never
    | had any SanDisk drive fail. Only WD :)
 
      | tentacleuno wrote:
      | I've very rarely had an SSD fail in general, to be honest
      | -- though I do generally stick to reliable brands[0], not
      | "Xykdidlwo" or "Dyewkdlo" off Amazon.
      | 
      | Right now I've got 3 SSDs in my server (2 mirrored so 1TB
      | for apps, and a 500GB boot drive), and I'm interested to
      | see which one goes first.
      | 
      | [0]: Crucial, Samsung, Kingston, SanDisk (until I hear any
      | information which discourages me) etc.
 
    | stephen_g wrote:
    | Yes, at least in terms of their memory cards for cameras etc.
    | I've really only heard them as being quite well regarded, as
    | far as I can remember...
 
    | justinclift wrote:
    | SanDisk used to have a good reputation, but after being
    | acquired by WD they've turned to shit:
    | 
    | * https://arstechnica.com/gadgets/2023/05/sandisk-extreme-
    | ssds...
    | 
    | * https://arstechnica.com/gadgets/2023/08/sandisk-extreme-
    | ssds...
    | 
    | * https://arstechnica.com/gadgets/2023/08/lawsuit-takes-
    | wester...
    | 
    | * https://arstechnica.com/gadgets/2023/08/sandisk-extreme-
    | ssds...
 
  | whitepoplar wrote:
  | What brand would you trust the most, for SSDs and for SD cards?
 
    | dharmab wrote:
    | There's only four flash manufacturers: Samsung, Micron, SK
    | Hynix and SanDisk/Kioxia. All of them have had problems over
    | the years. All of them will change the internals of products
    | without changing SKUs or anything visible to the consumer.
    | 
    | You best bet is:
    | 
    | - Buy a variety of manufacturers and SKUs
    | 
    | - Create backups regularly and test your restores
 
      | lazide wrote:
      | Also, always run perf tests (especially using large writes
      | - preferably up to the capacity of the drive!) for any
      | drive that it is important 'you got what you paid for'.
      | 
      | The number of counterfeit, badly designed to the point of
      | defective, or DOA SD Cards and SSD drives I've seen over
      | the last few years is crazy.
      | 
      | I literally won't even buy USB sticks anymore. The last
      | time I tried, all 5 different makes/models I tried were so
      | dysfunctional they were useless. Literally unfit for
      | purpose. Major brands too!
 
        | yjftsjthsd-h wrote:
        | Did you buy in person, or in an online marketplace (ex.
        | Amazon)? I only buy thumb drives at physical stores to
        | try and avoid outright counterfeits.
 
  | somat wrote:
  | I don't have any experience with their ssd's but I have a few
  | sandisk usb drives that have lasted far longer than any other
  | brand in that hellish environment of being an os system drive.
  | It is not really that bad but with the frequency that usb flash
  | dies when used as a boot drive you would thing I am abusing
  | them. The no-names I understand, junk from who knows where. but
  | the worst offender was kingston, they are probably fine on
  | windows as a rarely used backup unit. but as an openbsd system
  | drive, hot garbage, I went through 6 in six months, I would
  | expect better from a named brand. as a comparison I am still on
  | the original sandisk units, 5 years and counting.
 
  | lazide wrote:
  | Of the brands I've run across for SD cards, Sandisk has been
  | top 3ish for quality. I've never had major issues at least for
  | SD Cards?
  | 
  | Samsung has been catching up though.
 
| dboreham wrote:
| "resistors too big" ... 
 
  | layer8 wrote:
  | Tom's Hardware's fault. The original source only says
  | "components".
 
| bastard_op wrote:
| I stopped buying WD anything early 2010's, but then they acquired
| everyone else like Seagate, meaning even decent Hitachi disks
| would be now tainted to become typical WD garbage. I still won't
| buy anything WD, but alternatives are hardly attractive with the
| market limited to like 3-4 players.
| 
| Good old monopolies in effect, your options are bad or worse.
 
  | vanderZwan wrote:
  | I hadn't heard about the Seagate acquisition, that sucks. So
  | what are my options now if I want a reliable external hard
  | drive for example?
 
    | justinclift wrote:
    | Just to be clear, WD has not acquired Seagate. They're still
    | two different, competing, companies.
    | 
    | The above post probably typo-d "Seagate" while meaning
    | "SanDisk".
 
      | autoexec wrote:
      | I wondered if he was confusing the drama that happened with
      | Seagate buying up Maxtor. A lot of people were upset when
      | that happened because they trusted Seagate a lot more than
      | Maxtor or Western Digital and suddenly the same shitty
      | Maxtor drives many went out of their way to avoid were
      | being sold under the Seagate name leaving people stuck with
      | either buying WD or buying Seagate and probably getting
      | Maxtor anyway. Seagate's quality and reputation took a huge
      | hit.
 
        | coldtea wrote:
        | Or with this April Fools:
        | 
        | https://www.storagenewsletter.com/2014/04/01/seagate-
        | acquire....
 
      | qwytw wrote:
      | > WD has not acquired Seagate
      | 
      | Hasn't it?
      | 
      | https://www.westerndigital.com/brand/sandisk
 
        | beebeepka wrote:
        | Reading comprehension. SanDisk is not Seagate
 
    | rft wrote:
    | For external drives, I would seriously consider using SSDs.
    | Unless you use them exclusively as cold backups and handle
    | them carefully and seldom, I would be far too worried about
    | accidental drops. I have killed some external HDDs this way,
    | never killed an SSD, even though I am far rougher with them.
    | For extra reliability, buy two disks from different
    | manufacturers (e.g. Sandisk/WD and Samsung) at different
    | times and mirror the contents. Less chance of both disks
    | going bad at the same time.
    | 
    | Talking about 3.5" HDDs, sourced from external drives: WD is
    | still ok in my book. Both the Backblaze report [1] (newest,
    | quarterly version, check the drive hours, WDC has less than
    | HGST so far) and my own experience show they are ok. I used
    | to buy HGST based on Backblaze's reports, but now I am using
    | WD external drives in my NAS. My oldest and most used disk
    | (one of the parity drives) has more than 3 years power on
    | hours with nearly 900 start/stop cycles. It shows no signs of
    | failure so far.
    | 
    | I get these HDDs from external drives (called "shucking"),
    | 10TB WD My Book or WD Elements Desktop. It is a bit random
    | what you get, but between 7 HDDs (+1 currently in testing)
    | over about 3 years, I only had one non-Helium drive that runs
    | hotter than the other all Helium drives. No failures yet, no
    | bit errors as well, performance is at least good enough for
    | media storage, currently reading at about 180MB/s
    | sequentially.
    | 
    | I saw one problem: USB errors with WD's USB-SATA bridge and I
    | even had to remove the newest disk to run the test, it would
    | drop from the bus via USB. Might be because it is a
    | refurbished disk or something fishy with the USB 3.0 ports on
    | my server, so I won't blame WD for it.
    | 
    | [1] https://www.backblaze.com/blog/backblaze-drive-stats-
    | for-q2-...
 
    | asddubs wrote:
    | What's wrong with the WD ones? I have a bunch of them and
    | never had any problems
 
  | icehawk wrote:
  | I take it you mean "like Seagate [acquired everyone else]"
  | because Seagate, Western Digital, and Micron are all
  | competitors.
 
    | asmor wrote:
    | And don't forget Hynix. They somewhat recently got into the
    | B2C business, and while they command a premium, the SSDs both
    | OEM and Retail I use from them have been very solid.
    | 
    | There's also Samsung.
 
    | KennyBlanken wrote:
    | Seagate owns WD, and WD owns Sandisk...
 
      | icehawk wrote:
      | Seagate and Western Digital are both publicly traded
      | companies:
      | 
      | https://www.nasdaq.com/market-activity/stocks/wdc
      | 
      | https://www.nasdaq.com/market-activity/stocks/stx
 
  | AussieWog93 wrote:
  | It's funny you say that. I always thought WD were the more
  | reliable brand, and Seagate were trash.
  | 
  | I wonder if it's just a case of each of us having one HDD of a
  | particular brand fail on us violently, and then finding others
  | who were in the same boat.
 
    | tharkun__ wrote:
    | Pronounce this in German: "Sea gate oder sea gate nicht"
    | ("Sie geht oder Sie geht nicht"). Meaning "she works or she
    | does not work" is a German word play on early failure rates
    | for Seagate drives.
    | 
    | Coined when there was a time where if you didn't have Seagate
    | drives in a RAID you were more likely to loose your data than
    | not ;)
    | 
    | And yeah I started buying WD at that point. Backblaze stats
    | weren't a thing back then tho.
 
    | themagician wrote:
    | > I wonder if it's just a case of each of us having one HDD
    | of a particular brand fail on us violently, and then finding
    | others who were in the same boat.
    | 
    | That is absolutely the case and anyone with enough experience
    | could confirm it. Both WD and Seagate have made some real
    | trash drives, and both made at least one or two models that
    | were trash at scale. If you timed it just right you could
    | jump from one to another and experience massive failures with
    | both! You also probably have a drive from each that's been
    | running for 20 years _somehow_.
 
  | bayindirh wrote:
  | If Backblaze yearly disk stats and my personal experience in
  | our datacenter is anything of importance, WD is generally the
  | more reliable disk brand for the last decade or so.
  | 
  | I remember an era where Seagate Constellation (enterprise
  | disks) were so bad, I was replacing them a dozen per week.
  | 
  | Also, from my experience SanDisk didn't get tainted by WD
  | acquisition. Their Extreme Pro SDs still as reliable as before,
  | and their portable SSDs hit the speeds and reliability they
  | advertise.
  | 
  | Every manufacturer makes a design error almost once a decade.
  | Seagate did it, Maxtor did it, WD did it before (their drives
  | were _very_ finicky), however all big producers are in good
  | shape now, from my experience. I can equally trust a Seagate
  | IronWolf Pro or its WD equivalent, or a Samsung SSD and its
  | SanDisk equivalent.
  | 
  | Problems happen, PCBs got revised, things got recalled.
  | Everything is new, but nothing has changed.
 
    | justinclift wrote:
    | > Their Extreme Pro SDs still as reliable as before
    | 
    | Try this: https://news.ycombinator.com/item?id=38244389
 
      | bayindirh wrote:
      | These are SSDs. I'm talking about SD cards, which I just
      | downloaded my photos from my camera while writing this
      | comment.
 
| bastard_op wrote:
| The funny thing is since these have been getting news even months
| ago, there was almost immediate fire sales on all the main deal
| sites to sell them off. Everyone that bought them now have a
| waiting time bomb of a disk to use. Thanks Western Digital for
| your contribution to society.
 
  | hobobaggins wrote:
  | Costco was selling them (still!):
  | https://www.costco.com/CatalogSearch?dept=All&keyword=ssd
  | 
  | Is Costco completely unaware of these massive issues?
 
    | bastard_op wrote:
    | Blissful ignorance imho.
 
    | bastard_op wrote:
    | Costco is actually a decent org, and if anyone knew they were
    | selling this time-bomb garbage, they would stop it, as they
    | will warranty stuff for YEARS, just to be a somewhat decent
    | company in a time of pirates.
 
      | ben1040 wrote:
      | I own one of these disks and quit using it when the news
      | came out, expecting I should hang onto it to get money back
      | for a recall. Didn't even occur to me I could just have
      | brought it back to Costco all this time because of their
      | extremely generous return policy.
 
    | HankB99 wrote:
    | Maybe Costco caught up with this. I can't find it on their
    | web site (at least in the US.)
    | 
    | All I see is the "Extreme Go" which I presume is a different
    | product.
 
| bogantech wrote:
| > On the one hand, the resistors used in these SSDs are too big
| for the circuit board, causing weak connections
| 
| I am an electronics / PCB hobbyist and I can't for the life of me
| figure out how they came to such a weird conclusion. What does
| this even mean?
| 
| Larger components will have more surface area at the joint and
| should be stronger than a smaller component
| 
| > On the other hand, the soldering material used to attach these
| resistors is prone to forming bubbles and breaking easily,
| according to Hafele.
| 
| Never heard of solder doing this - it seems more likely to me
| that the solder wasn't reflowed properly in manufacturing.
| 
| What's more is that the component pictured is a capacitor.
| 
| The only conclusion I can draw here is that the guy has no clue
| what he's talking about
 
  | bravo22 wrote:
  | The most charitable way I can read their statement is that the
  | resistors are too large for the pad, and along with poor solder
  | material it forms a weak joint which breaks over time.
  | 
  | I have a hard time accepting that because there is not a lot of
  | heat on that line nor is there a lot of physical stress, like
  | constant vibration on SSDs.
 
  | jchw wrote:
  | Does seem a bit strange, but the original article[1] in German,
  | translated using Google Translate, reads as follows:
  | 
  | > "It's definitely a hardware problem. It is a design and
  | construction weakness . The entire soldering process of the SSD
  | is a problem," says Hafele. A hard drive has components that
  | need to be soldered to the circuit board. "The soldering
  | material used, i.e. the solder, creates bubbles and therefore
  | breaks more easily."
  | 
  | > "In addition, the components used are far too large for the
  | layout intended on the board," says Hafele, explaining the
  | technical problems: "As a result, the components are a little
  | higher than the board and the contact with the intended pads is
  | weaker. All it takes is a little something for solder joints to
  | suddenly break."
  | 
  | It sounds like what they're saying is that the solder pads are
  | too small for some of the components. Not sure about what
  | they're saying about the solder though.
  | 
  | [1]: https://futurezone.at/produkte/sandisk-ssd-ausfaelle-
  | western...
 
    | jeffbee wrote:
    | > It sounds like what they're saying is that the solder pads
    | are too small for some of the components
    | 
    | The converse is also possible. Instead of being a design flaw
    | with the pads too small for the component, it could be that a
    | larger component was substituted during manufacturing. Even
    | terrible freeware EDA packages have design rules that will
    | flag improper solder pad layouts, so it seems like what might
    | have happened is the physical part does not resemble its
    | model.
 
      | exmadscientist wrote:
      | > Even terrible freeware EDA packages have design rules
      | that will flag improper solder pad layouts
      | 
      | No, they don't. EDA software doesn't really know what size
      | the terminations are. It knows how big the pad itself is,
      | and is very good at keeping those out of trouble, but it
      | doesn't know what size the solderable area is. You might
      | tell it, or give it a 3D model, but make a mistake there
      | and you're right back here. As well, there are so many
      | different kinds of terminations (pop quiz: what kind are
      | these?) that even if it does know what size they are, it
      | doesn't necessarily know what size or shape the pad should
      | be.
      | 
      | Also the CM will totally edit this stuff and not tell you.
      | Which they're not supposed to do, and are probably better
      | at if you're a huge customer, but they still do it. EDA
      | sure doesn't know about _that_.
 
    | exmadscientist wrote:
    | > Not sure about what they're saying about the solder though.
    | 
    | There's more than one solder alloy in use. There's more than
    | one _class_ of solder alloy in use. Some are easier to use,
    | some are harder to use. Some are high-performance, low-
    | tolerance, some are low-performance, high-tolerance. Some are
    | expensive, some are cheap.
    | 
    | The most troublesome family is SnBi. These are relatively
    | new. They have a big "greenwashing" problem in that they
    | solder at lower temperatures, which is "environmentally
    | friendly" (and cheaper to run). Also the base metal is dirt
    | cheap. (Wonder why manufacturers are interested?) It's also
    | very, very brittle. It also happens to be a low-temperature
    | alloy... so it's much easier to get hot enough to desolder
    | during operation. Lots of trouble all around and in general a
    | very high field failure rate. Not recommended... oh wait but
    | it's cheap and greenwashable. Sigh.
 
  | nurple wrote:
  | If the correct amount of pad is not exposed at the edge of the
  | part, the solder will have nowhere to form a fillet which is
  | critical to its physical attachment. Solder is not glue, and
  | even with more pad contact beneath this is a physically weaker
  | connection which often results in tombstones like pictured in
  | TFA.
  | 
  | If you read the integration documents for these packages,
  | you'll see that they distinctly specify the requirements for
  | these margins. Probably the length is the more important axis
  | and may be what he was referring to when saying "large". I've
  | seen this be a problem particularly during the "chip shortage"
  | where jellybean parts like these capacitors have the weakest
  | specs in a design, meaning unilateral substitutions can happen
  | at many points in the design/mfg pipeline.
  | 
  | Indeed brittle solder is a real phenomenon which is often
  | easily visible in hand soldered joints that we call "cold"
  | joints. Formation of bubbles can happen for a number of
  | reasons, but IME it's the result of low quality solder or
  | flux/cleaning. The organic compounds gasify in the heat and
  | form an internal structure similar to bread.
  | 
  | ETA: an interesting paper exploring the cause and minimization
  | of voiding in the reflow process. Particularly, the decrease in
  | thermal conductivity in voided solder can critically contribute
  | to its failure in high-heat operational environments.
  | 
  | https://www.circuitinsight.com/pdf/controlling_voiding_mecha...
 
  | exmadscientist wrote:
  | > Larger components will have more surface area at the joint
  | and should be stronger than a smaller component
  | 
  | Larger components are also, well, larger, and have much bigger
  | forces on them. For ceramic capacitors you need to avoid
  | shearing and torquing as the body of the capacitor is very
  | brittle and a small crack means a dead part, possibly dead
  | short. Big ceramics are dangerous to use as they have a high
  | failure rate. I personally won't use anything larger than a
  | 1210. Some of my colleagues think I'm nuts and should stop at
  | 0805, but I think the flexible terminations available these
  | days make 1210 viable. At least in medium volumes, I don't ship
  | SSDs!
  | 
  | > I can't for the life of me figure out how they came to such a
  | weird conclusion
  | 
  | What I see when I look at this is they have a part with a
  | 5-sided termination (typical MLCC capacitor with metallized
  | cap) but they have a footprint that only gets fillets on 1 of
  | those 5 sides (typical would be 3). This is common for
  | resistors... but resistors (a) have only 3-sided terminations
  | anyway and (b) are made of robust alumina bodies, not fragile
  | ceramics. So someone either got dumb with the footprint library
  | or more likely overly aggressive to pack things in, not
  | appreciating what MLCCs really need to be happy. I don't think
  | it's part size changes, because the fillets along the length
  | dimension that are visible look about right in size.
 
  | onetimeuse92304 wrote:
  | I am electronics / PCB hobbyist and I can definitely see how
  | their explanation can be true. I can't say it is, but I can see
  | how it could be.
  | 
  | If you design a PCB for a given size of the resistor but then
  | decide to use larger resistors without redesigning the pads,
  | you may have reflow problems and weak joints. This is simply
  | due to the fact, that the components are positioned due to
  | surface tension during reflow process (they are pulled into
  | place as the solder melts). If the pads are for smaller
  | components, there will be too little solder for larger surface
  | and weight of the component and working at a wrong angle to
  | pull it into place causing potentially higher rate of failure.
  | 
  | > What's more is that the component pictured is a capacitor.
  | 
  | And that means what? From the picture I can tell that there is
  | very little solder between component and the pad. Potentially
  | too little to hold the component well in place.
  | 
  | > The only conclusion I can draw here is that the guy has no
  | clue what he's talking about
  | 
  | Maybe he does, maybe he doesn't. Have you considered a
  | possibility you are not an expert either?
 
  | londons_explore wrote:
  | It reads to me more like the journalist writing the article
  | summarized a technical report badly.
 
  | sheepshear wrote:
  | > What does this even mean?
  | 
  | It means you should click through to look at the pictures in
  | the original article.
 
  | bunnie wrote:
  | Hard to tell from appearance only but my initial impression is
  | that's an inductor, not a capacitor. The circuit looks like a
  | switching power regulator. The capacitors would be beige with
  | silver ends, this one looks like an over molded inductor,
  | similar to [1], and is used as the main power inductor in a
  | buck regulator.
  | 
  | If this is an inductor, my gut reaction is it has an
  | insufficient current rating for the application and it is
  | overheating. Inductors have a bunch of loss mechanisms that
  | contribute to heating. Depending on the type of metal used to
  | build the core, it can 'hard saturate' and effectively walk
  | itself off a cliff once the current draw gets too high. At some
  | point, it gets hot enough to desolder itself from the circuit
  | board. It's possible they did not see this in validation
  | because the power draw of SSDs depend heavily on the work load
  | and process variations in the chips; erase current can have a
  | fairly wide variation.
  | 
  | fwiw, voiding of solder joints is a problem. The solder is
  | applied as a paste - fine particles of metal solder suspended
  | in solder flux. During reflow the flux evaporates and leaves
  | the metal behind, but if the process isn't tuned right bubbles
  | of gas can be trapped in the joint. This can lead to
  | reliability problems. It can also increase the effective
  | thermal resistance to the circuit board, which for tiny
  | components like this can often be the primary path for heat
  | removal during normal operation.
  | 
  | [1] https://www.digikey.com/en/products/detail/pulse-
  | electronics...
 
| newaccount74 wrote:
| I told myself I'd never again buy a WD drive when I realised the
| WD Red NAS drives I bought were completely unsuitable for NAS
| because they secretely replaced the product line with SMR drives.
| 
| And now you are telling me that the Sandisk SSD I bought as a
| replacement also has a fatal design flaw? And apparently Sandisk
| is a WD subsidiary?
| 
| I'm feeling slightly less bad about spending a fortune on getting
| a bigger built-in SSD in my Macbook. Please don't tell me they
| are flawed as well.
 
  | layer8 wrote:
  | TFA is only about external drives.
 
    | newaccount74 wrote:
    | Yeah, I know, I replaced my NAS with external SSDs.
 
| jeffbee wrote:
| If that's really the issue, it's trivial to fix and you can pick
| these up for nothing in the secondary markets.
 
  | yetanotherloser wrote:
  | For you and, indeed, for me too. But, sadly, not for many
  | people.
 
| awiesenhofer wrote:
| Original article (translated via Google):
| 
| https://futurezone-at.translate.goog/produkte/sandisk-ssd-au...
 
| elzbardico wrote:
| I always found it somewhat amusing that SanDisk is very similar
| to to the french Sans Disque. Like the Chevrolet No Va situation
| for spanish speakers.
 
  | whoopdedo wrote:
  | That's entirely the point as flash or SSD are alternatives to
  | spinning platters of rust. It's storage sans disk.
  | 
  | The company was originally SunDisk but switched to avoid being
  | confused with Sun Microsystems.
 
| jbverschoor wrote:
| They "assured" me that mine won't fail. They checked the serial
| numbers, and they're not affected (3 disks).
| 
| Now I'm in the dark again
 
| CTDOCodebases wrote:
| I wonder if these drives were manufactured during the parts
| shortage?
| 
| Kind of makes you wonder what other devices are ticking time
| bombs.
 
| ChuckMcM wrote:
| One of the more interesting things to me is that while every
| storage medium has failures (which is why RAID and backups are a
| thing :-) there are more failure modes with flash storage that
| present as abrupt storage failure.
 
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