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Can someone identify this chip — Parallax Forums

Can someone identify this chip

abicashabicash Posts: 1
edited 2012-10-12 21:09 in General Discussion
Hi forum
My first post!! :)

I have been trying to repair an instrument and i am unable to identify a 14 pin chip.
I am attaching an image of the connected parts to this chip.
If someone could give me some pointers , i would be extremely glad

Thanks for your time
untitled.PNG
809 x 437 - 16K

Comments

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2012-10-12 00:23
    abicash,

    Welcome to the Parallax forum! What a great puzzle! My knee-jerk first impression was a 556, but the pinout just doesn't jibe. Another was a quad op amp. Though a tantalizing possibility, the pins aren't in quite the right order for that, either.

    -Phil
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2012-10-12 00:43
    Two clues in the schematic make me feel this is a prank.

    First, the power to the chip is +12 volts. There are logic chips that will accept this, but most are +5 or +3.3 these days.

    Second and more importantly, there is a potentiometer in series with a second potentiometer that appears to do nothing.

    That second item will either define this a genuine or prove this is nonsense. There are very few good functional schemes where two potentiometers are in series. So what is the purpose of that. And why not just have a resistor for the second one that appears not to use the adjustment on it?

    The fact that there are no values and all devices are either resistors or switches makes me wary. One has to decide at some point if the chip is digital, analog, or hybrid.

    I suppose one could investigate by trying to create a template of all 14 pins - two are power, and the others would all be either inputs, control, or outputs.
  • ercoerco Posts: 20,261
    edited 2012-10-12 00:44
    What's the instrument?
  • Clive WakehamClive Wakeham Posts: 152
    edited 2012-10-12 00:53
    The IC could be something like a 74LS107 Dual Negative-Edge Triggered Master-Slave J-K Flip-Flops.
    This chip has the clock triggering occurring at a voltage level so the pots could set the voltage level....
  • ercoerco Posts: 20,261
    edited 2012-10-12 01:32
    IIRC that's the Texas Dynamics Ionization Nebulizer IC for use with ionic abercrombic infitchulators. The twin series potentiometers Loopy noticed are provided to zero the PID setpoint for optimal photovoltaic rebuneration.
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2012-10-12 01:44
    Clive Wakeham wrote: »
    The IC could be something like a 74LS107 Dual Negative-Edge Triggered Master-Slave J-K Flip-Flops.
    This chip has the clock triggering occurring at a voltage level so the pots could set the voltage level....

    So one pot would be 'rough tune' and the other would be 'fine tune'. But a 74LS107 requires less that 7 volts.
  • GadgetmanGadgetman Posts: 2,436
    edited 2012-10-12 01:46
    The pots...
    Is one a big 'knob' and the other a small PCB-mounted 'trim' pot, maybe?

    I would really like to see a picture of the PCB, or the entire device, really.
    A closeup of the IC (showing any markings) would also help.
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2012-10-12 01:56
    Once again, too abstract... too vague. Erco's request of 'what is the instrument?' would clairfy a lot of what it might be.

    This is 14 pins and operates at up to 20 volts, but I dunno.......

    http://www.datasheetcatalog.org/datasheets/105/109379_DS.pdf
  • LawsonLawson Posts: 870
    edited 2012-10-12 07:23
    Any of the 4000 series logic chips are fine at 12 volts. It'd also be nice to have a closeup picture of the chip where it's installed. If your camera won't focus with a close enough shot to get details of the chip label, a hand magnifying glass works just as well for a camera as it does for your eyes.

    Lawson
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2012-10-12 08:36
    Pins 8, 9, and 10, suggest an op-amp unity gain voltage buffer: pot and trimmer connected to positive input, output connected to negative input. Pins 11, 12, and 13 suggest a comparator-type hookup: threshold set with positive input, negative input coming from pin 3 side, output driving an LED. Pins 1 through 6 are a mess, though, and don't conform to any known op-amp pinouts. abicash, are you sure you traced that part of the circuit correctly?

    -Phil
  • skylightskylight Posts: 1,915
    edited 2012-10-12 10:33
    erco wrote: »
    IIRC that's the Texas Dynamics Ionization Nebulizer IC for use with ionic abercrombic infitchulators. The twin series potentiometers Loopy noticed are provided to zero the PID setpoint for optimal photovoltaic rebuneration.
    Sorry erco but I think you missed the small "a" above the chip and so that makes it a
    Texas Dynamics De-Ionization Nebulizer IC
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2012-10-12 10:52
    Der putterspraken tibbulates the fliken flopen. Yah?

    Can we narrow it down by elimination?

    First of all it isn't a hex buffer or inverter as those have 6 pairs of i/0 and two power lines - a 16 pin dip.
    It is not a standard op amp chip (or is it)
    It is not a UNL darlington array as those have all outputs on one side and all inputs on the other.

    It could be a logic chip with multiple inputs and a sign output of some sort and multiple.

    Lets see. 14 pins minus two for power leaves 12. Either 3 devices or 4 devices or 2 devices.

    3 devices of 3 ins and 1 out
    4 devices of 2 ins and 1 out
    2 devices of 5 ins and 1 out

    Or 6 device of 1 in and 1 out. ? Wait a second I said that a hex device requires 16 pin dips. I made a boo-boo.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2012-10-12 11:17
    It's definitely not purely digital. You don't attach pots to gates. 'Might be mixed-mode, as suggested by the pull-ups, but the lack of caps tells me that it's not a timing chip of some sort.

    -Phil
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2012-10-12 11:23
    I am back to my first impression, a hoax.
  • RobotWorkshopRobotWorkshop Posts: 2,307
    edited 2012-10-12 11:38
    Loopy Byteloose wrote: »
    I am back to my first impression, a hoax.

    Or, it may be incomplete or not entirely accurate. If the existing part is soldered to the board then there may be hidden traces underneath, etc. Could be that 12V is a guess on the supply voltage. We could use some more details. What is the instrument? Is a custom home brew design or something more finished? What is the model #? Can the person provide any pictures? Close ups of the chip and board would help. Are there any markings on the chip or was it all sanded off to hide it?
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2012-10-12 11:46
    Relentless curiosity? Anything is possible, but this is a first time poster, and we haven't heard back from the OP. The schematic appears to be in something like Eagle, but the wires are poorly drawn as if it was very rushed and not much desire to verify correctness.

    We will just have to wait and see.
  • frank freedmanfrank freedman Posts: 1,983
    edited 2012-10-12 18:04
    Perhaps it is a comparator of sorts with a latch function (reset pushbutton maybe)?
  • ercoerco Posts: 20,261
    edited 2012-10-12 18:07
    Loopy Byteloose wrote: »
    I am back to my first impression, a hoax.


    A Snipe hunt to see how many manhours he can waste?

    I prefer a good wild goosechase myself.
  • Mark_TMark_T Posts: 1,981
    edited 2012-10-12 18:23
    The button controlling pins 5 and 6 strongly suggests one of the CMOS analog switch chips (selecting between different voltages to output on pins9&10, but not all the other connections make sense
  • Erik FriesenErik Friesen Posts: 1,071
    edited 2012-10-12 18:49
    Maybe the real riddle is who is masqerading as abicash? If its a real deal it needs pics.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2012-10-12 18:54
    Mark_T wrote:
    The button controlling pins 5 and 6 strongly suggests one of the CMOS analog switch chips (selecting between different voltages to output on pins9&10

    It's not a CD4051, '4052, '4053, or '4016/4066.

    -Phil
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2012-10-12 18:56
    Although the OP appears to have left the building -- abicash, where'd you go? You can't just drop stuff in our laps and then disappear! -- I don't think it's any kind of hoax.

    -Phil
  • ercoerco Posts: 20,261
    edited 2012-10-12 19:04
    abicash is on a treadmill somewhere with a model airplane, working on a completely different problem.
  • Erik FriesenErik Friesen Posts: 1,071
    edited 2012-10-12 19:51
    Maybe he's with browser.
  • idbruceidbruce Posts: 6,197
    edited 2012-10-12 21:09
    Browser beware.... Rumor has it that he is taking correspondence courses for taxidermy.
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