Can you help me identify components on a PCB?

Discussion in 'General Electronics Chat' started by trustno1, Sep 18, 2015.

  1. trustno1

    Thread Starter New Member

    Sep 18, 2015
    3
    0
    I have an LG E2251 monitor that keeps restarting when I turn it on. Problem started 3 days ago and I immediately stopped using it. I opened up the monitor and ran some tests to see what is going on. Components marked with red boxes in the picture below are making squeamish noises when the monitor is on. So I suspect those needs to be replaced along with nearby capacitors. However I can't identify what those components are. Any help would be greatly appreciated..

    20150918_215352.jpg
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,548
    2,373
    Inductive devices or chokes. Probabally μh values on them.
    Max.
     
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  3. ISB123

    Well-Known Member

    May 21, 2014
    1,239
    527
    Shielded SMD Inductors with their values on top.
     
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  4. trustno1

    Thread Starter New Member

    Sep 18, 2015
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    Where can I buy the replacements?
     
  5. MrSoftware

    Active Member

    Oct 29, 2013
    501
    123
    Non-expert opinion here: before you go replacing the inductors, check the capacitors carefully, especially those in the power supply. Capacitors are a very common component to fail. Bulging or leaking is a dead giveaway. If you've got access to an ESR meter then that might also help you determine if any are bad.

    If a capacitor is bad, the power might not be clean, and that might contribute to the noise coming from the inductors.

    For replacement parts, check out Mouser, Digikey, etc..
     
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  6. RichardO

    Well-Known Member

    May 4, 2013
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    I'm not convinced the inductors are bad -- They may be making noise because the power supply is cycling on and off at an audible rate.
     
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  7. analogdude

    New Member

    Jul 14, 2015
    14
    2
    I also doubt the inductors are faulty. They rarely fail. They can make audible noise if there is excessive AC or DC current.
    Capacitors possibly, or a fault in the converter or load.
     
  8. ian field

    Distinguished Member

    Oct 27, 2012
    4,415
    784
    It is indeed an inductor in uH.

    The markings follow the same convention as resistor colour codes; the first 2 digits are both 2, and the final 0 means that it isn't multiplied by anything - so just 22uH.
     
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  9. trustno1

    Thread Starter New Member

    Sep 18, 2015
    3
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    Thank you all for helping me identify the components. Once I recieve them, I'll replace the parts and let you know if its working or not :) Thank you people!
     
  10. ian field

    Distinguished Member

    Oct 27, 2012
    4,415
    784
    Before I got an ESR meter, I often found dud electrolytics by temperature - they often run hot when starting to fail.
     
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