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[SOLVED] Ground / 5v Short :: Step 16

supercollidersupercollider
edited January 2015 in Troubleshooting
My solder joints I all checked and it looks fine to me. Anyone have a suggestion on where the most likely culprit area would be?

Voltage test was exactly 5v

Thanks :)


Comments

  • julianjulian
    how did you measure the short?
    if there is a short your voltage test would not read 5V.
    what is the resistance between gnd and 5V?
  • supercollidersupercollider
    edited January 2015
    Short was measured using a multimeter and the beep test.

    Sorry, perhaps I wasn't clear. At the initial voltage test after finishing the power supply I read 5v. After constructing the rest of the board, I did the continuity test, and discovered a short. However, I plugged it into the power supply anyway (I like to live dangerously), and I still read 5v....

    Resistance between ground an 5v at the point in step 16 is a little less than 1 ohm. The only other point on the board which has the same behaviour is at the display connector between pins 1 and 2. Which I guess are ground and +5v?
  • julianjulian
    edited January 2015
    1 ohm is definitely a short somewhere
    I'll have a closer look on your picture
  • julianjulian
    ICs are not inserted yet I guess?
    hard to spot tiny solder bridges on the picture you provided... but my guess would be that'S what causes a short.

    maybe try to reheat suspicious looking solder joints and make sure no solder joints touch their neighbours.
    resistance between gnd and 5V should be at least a few hundred ohms

  • julianjulian
    the soldering on the IC between the 2 mainboard conectors looks a little bit suspicious.
    like the upper left 2 pins touching on the pic.
  • supercollidersupercollider
    edited January 2015
    I reheated every joint on the board, and and now have 3.5 ohms across ground and+5v. 

    I get 5 ohm when I reverse the pins of my multimeter....

    some closer pictures:


    I have the same short across the potis, and the expansion header
  • supercollidersupercollider
    Bump.
  • supercollidersupercollider
    Result - broken multimeter, no problems at all.
  • julianjulian
    hahaha not really
    #-o

    Glad it is solved.

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