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Lobotomized Prop — Parallax Forums

Lobotomized Prop

TubularTubular Posts: 4,726
edited 2011-09-23 20:42 in Propeller 1
Just in case you're desperately wondering how those signals get from die to pin...

Err.... is there any punishment for doing this barbaric act to a perfectly operational propeller? Or is it just bad karma?
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Comments

  • Duane DegnDuane Degn Posts: 10,588
    edited 2011-09-19 17:12
    So why didn't you go all the way to the center?

    Just to prolong its suffering?

    It looks like the die is still encased. Is you method of removing material precise enough to be able to still see the die if you removed the center material?

    Those leads leading to the pins are thicker than I thought they'd be. Interesting pictures.

    Are your other Propeller chips behaving better now they know how vicious you can be?

    Duane
  • jazzedjazzed Posts: 11,803
    edited 2011-09-19 17:30
    Prelude to a DIP28 version?
  • TubularTubular Posts: 4,726
    edited 2011-09-19 18:14
    Jazzed, I hadn't thought of that, but I'm sure it would still work. Sawn-off props, eh? Too bad we're always needing more pins.

    I was kind of hoping if I opened it up, I would find some little stubs for the mythical port B, just waiting to be connected.

    Duane, I like that idea, kind of like hanging dead fox skins along the fenceline. I might store that prop in the drawer next to all the good ones and see if the good ones run faster :)

    And I'll send it back to the workshop to open up the middle just for interest sake.
  • RinksCustomsRinksCustoms Posts: 531
    edited 2011-09-19 19:18
    lol, looks like someone got a new belt sander!
  • frank freedmanfrank freedman Posts: 1,983
    edited 2011-09-19 20:48
    Tubular wrote: »
    Just in case you're desperately wondering how those signals get from die to pin...

    Err.... is there any punishment for doing this barbaric act to a perfectly operational propeller? Or is it just bad karma?

    Objection! ! !

    Oh, sorry, guess it is a bit to late to ask whether it got a fair trial or not.......
    Wonder what its offense was?

    Frank
  • Cluso99Cluso99 Posts: 18,069
    edited 2011-09-19 21:08
    I too was going to ask what that poor little chip was guilty of.

    I wonder if you could just glue this chip to another prop and get some extra I/O pins??? hahaha
  • Toby SeckshundToby Seckshund Posts: 2,027
    edited 2011-09-20 12:00
    And there was me thinking I was being silly to suggest, to Cluso, that a nail through the top ("X marks the spot") a while back was a way to access some more outputs.

    I could have done this to the poor one that I tested at 9 Volts, as an autopsy.
  • Cluso99Cluso99 Posts: 18,069
    edited 2011-09-20 13:53
    Touch wood... I have never killed a prop so to do this on a live prop would be a criminal offence :-)
  • TubularTubular Posts: 4,726
    edited 2011-09-20 14:05
    No offence committed, Frank, but (just like a horrific medical experiment from the 18th century), this is being done in the name of "science".
  • TubularTubular Posts: 4,726
    edited 2011-09-21 17:54
    As promised, the same chip opened up a little further, showing the orientation of the die.
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  • TubularTubular Posts: 4,726
    edited 2011-09-21 17:58
    Close up...
    Its upside down (pin 1 is top right direction)
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  • Duane DegnDuane Degn Posts: 10,588
    edited 2011-09-21 18:11
    Thanks for the update. Very interesting.

    I like the way you preserved the beanie cap as an identifier.

    I hope new forum members know you're capable of using Propellers in a friendly manner.

    Duane
  • Cluso99Cluso99 Posts: 18,069
    edited 2011-09-21 18:51
    I wonder if you could solder to the pads of the die and make it work???
    Are the connections under the die???

    Now, are you trying to recover the program data from the chip???

    Perhaps you could buy some dies direct from Parallax to save the trouble.
  • TtailspinTtailspin Posts: 1,326
    edited 2011-09-21 19:25
    oh, look at that, you can see where the cogs were rubbing together... Your customization should make it much easier to lubricate now.. :lol:

    -Tommy
  • TubularTubular Posts: 4,726
    edited 2011-09-21 19:48
    Lol...

    Cluso... by my estimate (from the flylogic image) the connection pads on the die are something like 0.10 ~ 0.12 mm square. So we're talking half a 0201 component width. But stranded hookup wire has 0.13mm strands, so perhaps there is hope :) Or perhaps we could design a pcb to match up with the pads and mount the die facing down... you would need ~ 4 mil tracks which is not impossible.

    The die is surprisingly large... heading towards 7x7mm I think, so can't be much spare room in the QFN pack which is 9x9mm

    Something else that has me wondering:- for QFP and QFN packages there are 4 pairs of power pins, and matching double connection pads on the die. But for DIP only the "middle" pairs between P7/P8 and P23/P24 are connected. This has me thinking the QFP power inputs between P15/P16 and P0/P31 may be "not as important" with respect to decoupling and supplying power. Alternatively the additional decoupling might mean QFPs can run smoother than DIPs?
  • Toby SeckshundToby Seckshund Posts: 2,027
    edited 2011-09-22 11:46
    The good news is that I think I have spotted the fault.

    I recon that R8 needs replacing.
  • frank freedmanfrank freedman Posts: 1,983
    edited 2011-09-22 11:56
    An alternate possibility is that this is part of an attempt to lock up the record for producing the smallest stackable prop chip assembly. Wonder where the xtal will be mounted?
  • Cluso99Cluso99 Posts: 18,069
    edited 2011-09-22 20:05
    Toby: I am wearing my microscope glasses but I just cannot seem to locate R8. Which spec is R8 ???
    Frank: No need for an external xtal - we are using the internal one. No need for an eeprom either - we are loading all chips in parallel with another big prop - these dies are just to be stacked on top of one another like a sandwich.

    However, I think we need to avail ourselves of the machine Chip has to make the parallel connections between the stacked dies ;)
  • frank freedmanfrank freedman Posts: 1,983
    edited 2011-09-23 13:05
    Cluso99 wrote: »
    Toby: I am wearing my microscope glasses but I just cannot seem to locate R8. Which spec is R8 ???
    Frank: No need for an external xtal - we are using the internal one. No need for an eeprom either - we are loading all chips in parallel with another big prop - these dies are just to be stacked on top of one another like a sandwich.

    However, I think we need to avail ourselves of the machine Chip has to make the parallel connections between the stacked dies ;)

    I would loan you my nano-drill so that you could create your own through-silicon holes thereby keeping ALL connections within the confines of the die size, but with ITAR, shipping costs, insurance and etc. you may be better off at harbor freight or home depot for a substitute tool for use here.

    Frank
  • Cluso99Cluso99 Posts: 18,069
    edited 2011-09-23 14:14
    frank freedman wrote: »
    I would loan you my nano-drill so that you could create your own through-silicon holes thereby keeping ALL connections within the confines of the die size, but with ITAR, shipping costs, insurance and etc. you may be better off at harbor freight or home depot for a substitute tool for use here.

    Frank
    Great idea Frank! Maybe we could get chip to add the holes in propII to save us the trouble there ;)
  • RinksCustomsRinksCustoms Posts: 531
    edited 2011-09-23 20:06
    ..my bad, i take that back. Looks like someone got ahold of a milling machine, lol!
  • TubularTubular Posts: 4,726
    edited 2011-09-23 20:42
    Well picked RC!

    Or as I like to think of it, a poor mans' FIB (focused ion beam)... with somewhat poorer 'focus', and iron rather than ion for that matter.
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