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My Maxtor Hard Drive Just Caught Fire!
Dracos writes "Dell batteries you say catch fire? Well don't worry about that Dell battery, look inside your PC case at your HDD, mine just went up in smoke and flames..." Could be worse. It could be ball lightning. I hear there's a lot of that going around inside servers these days.
Ive worked as a tech for 10 years now, and for every 1 problem I've seen with a Seagate or Western Digital, I see 3 problems with a Maxtor. Both in retail sales and repair, I've just seen too many problems with Maxtor's over the years. They fail about 3x as much as any other brand.
I know there's people out there who have had problems with all the brands, but overall in tens of thousands of drives I've sold or replaced, the majority of those are Maxtors. A few collueages of mine who also have been doing PC repair for 10+ years also have had the same bad luck with Maxtors.
This doesn't really suprise me. Although none of my clients' machines will be affected by this, as I haven't put a maxtor in a machine for god knows how long.
One chip baking is definitely not anything near the danger of a battery baking. Lithium rechargables are pretty dangerous if misused. One EE battery specialist told me that you only need to overcharge a lithium battery by about one percent to risk explosion or damage, which is why the charge limiting circuitry is so important.
I read TFA, and from what I understand, is drive died normally (or a cable came unplugged), like lots of drives do, and when he plugged it in "while it was out of the case" as he says, the contacts on the logic board must have short circuited on the metal surface of the case, which created some sparks. It happened to a friend (who happens to be a computer tech) once when he was checking a faulty drive.
So in essence, he was not careful with his drive. Hardly a Slashdot story, even less news.
the picture of hard drive looks familiar to me. I have seen some of them. One of my friends was analyzing why they fail several years ago.
And basically they reached two answers. Some of the companies have replace the halogen based flame retardants with phosphorus based flame retardants due to environmental reasons. Some of the phosphorus based flame retardants are phosphates. And the phosphates segregate out of the epoxy used to embed the die under certain heat and humidity conditions. When there are enough phosphate leached out, it shorts the leads of IC. If you are lucky, you can get the power leads short and the IC is on fire. So in short, the new flame retardant set the IC on fire. This condition happens in summer mostly because of the higher humidity.
And the second reason was that some of the IC makers have replaced the lead based solder with lead free solder due to environmental concern. Most lead free solders are tin rich. And tin grow whiskers. The tin whisker can short leads. Again, if you are lucky, you get power lines short and you get fire.
Yesterday a friend told me that the Sony battery was also short by whiskers. I didn't understand where comes the whiskers though.
There is a spark in every single flame bait point.
What happened there looks like he fried the power drive chip.
Lets see - All HDD PCB's have on it a power drive chip, that involves some rather large internal transistors for head positioning, and spindle rotation.
Durning fast seek situations, or spinning the drive up, these can dump a lot of current through them, on the order of 1A to 1.5A (talking 3 inch single platter drives here, YMMV)
That said, the power drive chip usually has some rather huge transistor arrays associated with controlling all that juice. Those power drive chips are generally done in either bipolar or DMOS silicon (DMOS, not CMOS, it is a power transistor process for large high voltage, high current transistors.)
Sometimes the current distribution across the transistor array is not balanced and you fry the transistors. (For the semiconductor folks - hot Vbe junction, without emitter resistance ballasting, to give current balalnce, leading to a a domino effect across multiple base-emitter junctions burning out)
What happens when the transistor fries, is that the chip inside the package gets hot enough that the plastic package above the chip melts, and then gassifies. Ka-boom!!! The gas blows a hole thru the top of the chip's package.
Been there, done that.
www.effectiveelectrons.com "chips that work" Analog, RF, Mixed Signal