Bunnie Melts Some microSD Cards

Bunnie shows up with a microSD card looks like under the hood. We've got a new VoiceBox shield for Arduino, e-ink type displays, USB motor controllers, and a couple DC muffin fans.

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Gray market parts are a problem for all folks playing with hardware bits. For Bunnie Huang (leader of the 2009 Geek Tour), it caused problems for Chumby and he does not take these problems lightly.


With a little nitric acid and a high power microscope Bunnie starts to piece together why some microSD cards work and others mysteriously don't. From those observation he then tries to connect the dots within the razor thin margins of the microSD industry:

"I?d like to point out to casual readers that the spot price of MicroSD cards is nearly identical to the spot price of the very same NAND FLASH chips used on the inside. In other words, the extra controller IC inside the microSD card is sold to you ?for free?. The economics that drive this are fascinating, but in a nutshell, my suspicion is that incorporating the controller into the package and having it test, manage and mark bad blocks more than offsets the cost of testing each memory chip individually. A full bad block scan can take a long time on a large FLASH IC, and chip testers cost millions of dollars. Therefore, the amortized cost per chip for test alone can be comparable to the cost of silicon itself."

It's as if McDonald's created so many hamburgers that it would be cheaper for them to smother the burgers in 'special sauce' (added cost) than it would be to make sure (test) the hamburger tasted good. Oh wait..

We gotta get our hands on some nitric acid and a good microscope!

The VoiceBox shield says "Ready - all your base are belong to us"!

New VoiceBox Arduino shield. Make your project talk like Stephen Hawking.

We are very interested in e-ink and low power displays. While E-Ink doesn't want to deal with us (we've tried!), Kent Displays seems to have a very similar, zero-power retention display. These are not cheap! But it's really weird to see these displays display a full graphic screen, and then remove them from power. We're working on action shots and example code but we couldn't resist posting these! Offered in a very large 320x240 pixel and 240x160 pixel displays.

Pololu has released some really nice little motor controllers. The Maestro is a simple to use 6-channel servo controller, and the Jrk 12v12 can handle up to 16V and 12A all over USB!

A couple new 5V DC 'muffin' fans for cool or jello chopping. Your choice.

Be sure to checkout our new products list for a easy way to see all the great widgets we're getting posted.

Comments 12 comments

  • JayKominek / about 14 years ago / 3

    My wife and I own a forensic toxicology/chemistry company here in Boulder; I'm pretty sure we've got the acid and microscope on hand. (For bonus points, we've also got a fume hood and trained chemists.) If you've got something you're interested in investigating, let me know, and I'll see what we can do.

    • (feverishly digging through parts bin) Jay! Thank you so much. We will find something interesting for inspection and ask for your assistance.

  • edwardrford / about 14 years ago / 2

    ^^ Most. Awesome. Comment. Ever.

  • NXTreme / about 14 years ago / 2

    The counterfeit parts scam reminds me of another post on the SF website back in 2008. I did a little research and it is very scary how easy it is to get fake chips in almost everything you buy. Just think, those chips are controlling the ABS brakes in your car, in the jets you fly in while going on vacation, maybe even in the computer your reading this on. Find the other post here.

  • alxxx / about 13 years ago / 1

    How about talking to pixelqi ?
    Their displays like the one in the OLPC are awesome!!!
    They are talking about designing a $100 hdtv.
    Start selling their screens and sign me up for two please.
    Think 10" , readable in full sun , downmode LC , full colour, normal LCD, or a black and white e-ink-like display at the flick of a switch. One of these plus beagle board or gumstix overo would make an awesome portable.
    And why don't you guys resell gumstix while your at it ?
    When can I get a developer Kit for your 10" screen, or even just see a demo of it?
    Developer kits have been shipping since early summer 2009. Please contact vivek@pixelqi.com for more information

  • mentor / about 14 years ago / 1

    If you think it's weird to remove the power from a Kent display and see its full graphic image remain, you should see the Kent "InfoSign" display I got for development of a product back in 1997, and which still sits in my "junk drawer". That year marked the last time the prototype display was powered from any source, and it is still displaying the same image I put on it during development testing 13 years ago!

  • WimL / about 14 years ago / 1

    Oh cool. I've been interested in cholesteric LCDs for a while as a more hobbyist-accessible alternative to e-ink but the only suppliers I could find at the time weren't selling in onesies. (I think I wrote to sparkfun about them a year or so ago :) )

    • Thanks for the recommendation! We're pretty impressed with the technology but the price is almost a killer. We hope to find additional cool displays in the future. Let us know if you hear of anyone.

  • AndyTau / about 14 years ago / 1

    Instead of eInk did you try with SiPix (www.sipix.com) ?
    They have some very interesting products ...

    • Thanks for the pointer! We've been hoping to find a flexible solution as well. I've pinged SiPix and hope to hear from them soon.

      • tj / about 14 years ago / 1

        There is also another company called Pixel qi that seems to be offering a new technology (Eink + color+ option to turn lcd on/off). It would be great to get their products on SFE.
        (The website does not provide much info, but maybe the sales rep will do some talking)

  • kitscuzz / about 14 years ago / 1

    So I work on a robotics team and we build this underwater vehicle (check us out: http://ram.umd.edu ). One of the things we always joke about is putting an underwater speaker on the robot and having her play music at the competition for the divers, but seeing the speech synthesis chip gives me the desire to make the robot ramble about what she's up to as she navigates around.
    I can see it now, there's some terrible error and the diver hits the kill switch "Wait, I was doing such a good job! Put me back! Let me try again!"

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