Can I ask here for chip identification?

Discussion in 'General Electronics Chat' started by samm86, Oct 29, 2010.

  1. samm86

    Thread Starter New Member

    Oct 29, 2010
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    Hello all, I'm new here. I want to ask for help in identifying a chip. If this is the wrong place for that, please let me know and I will go elsewhere. I have a chip that fried on my Driver Information Module in my Cadillac. The module is $200+, so I tore it apart to see if I could replace a cheaper part.

    I found this:
    http://www.flickr.com/photos/55264098@N07/5126779603/

    It's hard to make out, but the lettering is:
    0513
    I <Symbol, maybe NOT gate?> R 041D
    13 31

    The circle on the bottom has "9K" stamped into it.

    Thanks for any help.
    SAM
     
  2. tom66

    Senior Member

    May 9, 2009
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    That's a pretty bad failure. It looks like it almost incinerated itself. That is rare in electronics; it's quite likely if you replace it, it will fry itself again unless we're dealing with a rare fault...

    The I <not gate> R is the symbol for International Rectifier (the <not gate> is actually a diode.) They usually make MOSFETs, diodes, and other similar active components. The good news is the component will be sub $10 most cases, the bad news is it looks like the part number has been completely incinerated so it will be very difficult to identify it.

    However, if you can post a picture showing the traces (wires on the PCB) to the device, we might be able to make an educated guess as to what it does.

    This forum does have some rules on automotive electronics, but as this repair would not endanger the vehicle it would probably be okay - what does this module do? Might want to get moderator approval to make sure.
     
  3. samm86

    Thread Starter New Member

    Oct 29, 2010
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    Wow, thank you for that very informative response. You're very helpful indeed.

    I understand the automotive rules, and I assure you, this is legit. The DIM controls the Radio/Climate Control backlighting (among many other things) for the dash. 3 years ago, I installed a Cadillac factory navigation system in my car, which before had just a CD player. Since this was the case, a certain wire in the radio harness had to be cut prior to installing the nav. I didn't know this at the time, so I installed the nav and my interior backlighting didn't work. Found a burnt 10A fuse in the fuse box, replaced it with another 10A, blew right away.

    Then I did the unspeakable - I replaced it with a 20A fuse. Before long I smelled burning electronics...

    We at the Cadillac Owners forum have discussed this in detail, and went through the wiring diagrams to deduce the problem to the DIM.

    Beyond that, I can't tell you what this single chip does - I simply don't know. I do know that the DIM controls the backlighting, which I would like to finally fix 3 years later.

    Thanks
    SAM
     
  4. tom66

    Senior Member

    May 9, 2009
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    Now you know why you use the right fuse value! I guess it's the hard way to learn a lesson.

    Thanks for the information. The device is probably a MOSFET from this, though it could be a BJT or even a diode (or diode pair), it seems less likely. What kind of lighting are we talking about? Small LED lights or very bright lights? Are the lights dimmable? (If so, it's probably using a PWM system.) If the exact part number can't be found it may be possible to replace with an equivalent. It may be that it's a part made specifically for Cadillac - car manufacturers can often request this if they're making 100k+ units.
     
  5. samm86

    Thread Starter New Member

    Oct 29, 2010
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    I'm guessing they are small LEDs, and I'm not sure if they are dimmable - you see the display for the radio and CC are dimmable, but I'm not sure the backlighting for the buttons dims as well...

    I don't want to jump to the conclusion that this chip is used specifically for lighting. However, given that everything else works OK in the car (everything else that the DIM controls), perhaps this chip was specifically designed for the lighting. I know the part number isn't readable in the picture, but what about what I've written in the first post? Is that enough info to figure out what this chip is?

    Thanks
    SAM
     
  6. tom66

    Senior Member

    May 9, 2009
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    The device isn't a chip, it's basically an electronic switch (from what I can gather), so you'd call it a transistor. Anyway, what I'm talking about is do the LED's dim when say you turn the headlamps on, or if there's a light sensor, when it gets dark. (To improve outside visibility some cars automatically dim the dashboard and button lights.)

    Either way it doesn't hurt to include too high (current) rated a MOSFET, it only costs slightly more money (you could be looking at up to $5 for one of the more powerful ones. Price becomes impressive when you consider the performance that these devices have.)

    Can you take a picture of the bottom and the top of the board, birds eye view? Need to see the connections to verify it's a MOSFET.

    I'm going to bed now, so I'll try and reply in the morning. 'night all.
     
    Last edited: Oct 29, 2010
  7. samm86

    Thread Starter New Member

    Oct 29, 2010
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  8. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    From looking at the bottom side, I'd have to go with MOSFET. I am also concerned that the amount of current required for a meltdown/crack of multiple MOSFETs probably took some of the smaller SMD resistors out as well. Do you have a better focused image of the area of the MOSFETs from top and bottom, attempting to minimize/remove flash bounce? Maybe take a photo while outside?
     
  9. samm86

    Thread Starter New Member

    Oct 29, 2010
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    There are no more burnt spots on the board at all, if that's what you mean... This appears to be the only damaged spot.
     
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