Problems with fried components on a HP 2510p motherboard

Discussion in 'General Electronics Chat' started by telefon, Jan 22, 2011.

  1. telefon

    Thread Starter New Member

    Jan 22, 2011
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  2. thatoneguy

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    Feb 19, 2009
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    You bumped an old thread, should have created a new one with a link to this one, but the mods should take care of that for you.

    The T1IG appears to be an ST Micro MOSFET, though I cannot pin down a datasheet, it's for PWM Switch mode power supply switching.

    Google pretty much only shows this thread as a result for a search on the engraved number.

    Keep in mind that another device most likely failed to cause the catastrophic failure shown in your images.

    Is your board out of an instrumentation device? It has several unusual connectors, and a glaring lack of smoothing caps if the MOSFET was used for a switching supply. Have you tried contacting the manufacturer to see if it is in warranty? Or at least to see what that part is?
     
  3. SgtWookie

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    Jul 17, 2007
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    Don't know about the T1IG part, but the 47k SMT resistor (black, marked 473) to the left of it has cracked solder and the end is damaged; it needs replacement.
     
  4. thatoneguy

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    Found it. Fixya has info Seems to be a common issue with that notebook.

    STSJ60NH3LL $1.97 at DigiKey

    Datasheet says it is an obsolete component, but I couldn't find a current one with the same package/pin layout as described in the fixya link.
     
  5. thatoneguy

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    I put my kindergarten level artist skills to work on it.

    This part is for Search Engines: T1IG or T11G or TIIG or TI1G labeled acceptable SMD Replacement is STSJ60NH3LL N-channel 30V - 0.004Ω - 15A - PowerSO-8™ STripFET™ Power MOSFET for DC-DC conversion.

    Lots of non-shiny solder joints in that area, which means those components came close to or passed the melting point of reflow solder (sometimes as low as 200 degC)


    [​IMG]
     
  6. telefon

    Thread Starter New Member

    Jan 22, 2011
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    Oh, thanks for the responses! :)

    Well, I will see if its possible to get some new components here in sweden and if I'm able to do something about this.

    Otherwise I have to get a new motherboard i guess..
     
  7. SgtWookie

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    Nice find, Thatoneguy. :)

    As far as the solder looking like it reflowed ... all of Europe (and likely Asia, too) has gone to RoHS compliant components and solder, which means no lead (Pb). Going from Sn63/Pb37 to Sn96 (or other lead-free solder) was pretty rough at my workplace (not HP); getting the reflow oven temp vs conveyor rate just right for each board type was a real challenge.

    Sn96 requires a much higher temp than Sn63/Pb37 to reflow, and it was a very fine line between getting a good shiny joint and killing parts. The different heights of components on the boards and varying amounts of solder in areas would cause the peak temps to vary around the board. Rework was kept pretty busy with their soldering irons, reflowing stuff by hand.

    Just because the surface looks grey/gray doesn't necessarily mean that the joint is bad. What one has to look very carefully for (often under a microscope) are cracked solder joints, as the 47k resistor I pointed out - but it had a damaged end, as well. There are also some other parts that look like the solder under them have cracked (you circled one of them) which do need to be re-flowed.

    I do great with Sn63/Pb37 solder. I can make Sn96 much of the time, but it requires a good bit more effort. If I'm repairing a board I own, I'll flow a bit of 63/37 on a defective components' connections to make removal a lot easier.
     
  8. bertus

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    Apr 5, 2008
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