[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)
(HTM) web link (www.tomshardware.com)
(TXT) 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?
| </Anakin-Padme meme>
| 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" ... <accompanied by picture of a capacitor>
| 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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