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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.
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.
That chip you're looking at is a STMicro "SMOOTH" combo driver, most likely slightly customised for the application. This particular chip has two power regulators and a serial interface to the microcontroller (most likely I2Cish) in addition to the motor drive stuff.
Also, brushless DC motor drivers that have the drive transistors and the PID controller in the same package have been around for years (Hitachi and SGS were making them back in the late 1980s/early 1990s); the trick was getting them on the same chip as the coil driver, which is more like a BTL audio amp than a motor driver (Seagate actually did use a car audio amp, the TDA1210 I think, in the early ST4000 series drives back around 1984).
-lee