Empty Solder Hole?? Why?

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  • pnutbutters
    Member
    • Jun 2012
    • 17
    • usa
    #1

    Empty Solder Hole?? Why?

    I have a power board for a flatron LG monitor

    One side of the board has a chip that is completely missing solder from the through hole..

    Could this be correct? Or should I fill it with solder and see if that fixes the issue..
    Tags: None
    • t.j.
      Badcaps Veteran
      • Apr 2010
      • 383
      • canada
      #2
      Re: Empty Solder Hole?? Why?

      so there a chip/cap there an no solder on one leg? if yup! i would think that would be a bad contact point an would solder it! or with unit run it! use piece of plastic an put pressure on it an see if makes difference!

        Comment

        • pnutbutters
          Member
          • Jun 2012
          • 17
          • usa
          #3
          Re: Empty Solder Hole?? Why?

          Originally posted by t.j.
          so there a chip/cap there an no solder on one leg? if yup! i would think that would be a bad contact point an would solder it! or with unit run it! use piece of plastic an put pressure on it an see if makes difference!
          I think it's actually a chip, probably a power regulating chip of some sort. but any component that has a leg coming through the board should have solder to fill it yeah?

            Comment

            • crtfool
              Senior Member
              • Jun 2010
              • 82
              • USA
              #4
              Re: Empty Solder Hole?? Why?

              Do not solder that leg if it never had solder! I have seen this many many times - it is a function of the chip that is not used in that installation, and soldering it may do nothing......but, it could do a lot of damage!

                Comment

                • mariushm
                  Badcaps Legend
                  • May 2011
                  • 3799
                  #5
                  Re: Empty Solder Hole?? Why?

                  Some power regulators have a pin that's an optional function (adjustment of voltage output) - by default the chip converts any voltage to a value preset in the chip like 5v or 3.3v but if there's a resistor connected to that optional pin, the chip will output a value different than the default, like 2.8v for example.

                  On other chips, that pin is connected to the metalic pad that's usually connected to a heatsink. The monitor manufacturer may purchase chips that perform a certain function from various manufacturers, where one kind of chip may use that unsoldered pin while the other chip may not use it.

                  ex 12v to 5v linear regulators

                  chip 1: input - adjust - output , tab = ground

                  chip 2: input - ground - output , tab = ground

                  chip 1 can be either fixed 12v to 5v or it could be for example 12v to 9v with adjustable pin connected to resistors to lower the default 9v to 5v
                  chip 2 must be fixed 12v to 5v ...

                  depending on the chip type, they may or may not solder the adjust pin to the board to generate at output 5v

                  So no, don't solder anything where it seems there was no solder initially.
                  Last edited by mariushm; 06-23-2012, 07:47 PM.

                    Comment

                    • t.j.
                      Badcaps Veteran
                      • Apr 2010
                      • 383
                      • canada
                      #6
                      Re: Empty Solder Hole?? Why?

                      sorry for the bd info! should have asked if it looked like there was a solder puddle on pad!

                        Comment

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