Copper pads on printed circuit board came off.

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • topfli8979
    Badcaps Veteran
    • Oct 2012
    • 311
    • USA

    #1

    Copper pads on printed circuit board came off.

    I was in the process of removing some fets on a printed circuit board, and I guess applied to much heat. The copper pads on the top and bottom came off the board, and are were destroyed. Now I cannot get the solder to adhere to the board properly. Is there a fix for this, or do I have to replace the board?
  • tom66
    EVs Rule
    • Apr 2011
    • 32560
    • UK

    #2
    Re: Copper pads on printed circuit board came off.

    You need to find the nearest copper connected to that, and strip the soldermask off, then solder to that. Pictures of the board would help.
    Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
    For service manual, schematic, boardview (board view), datasheet, cad - use our search.

    Comment

    • topfli8979
      Badcaps Veteran
      • Oct 2012
      • 311
      • USA

      #3
      Re: Copper pads on printed circuit board came off.

      Here it is.
      Attached Files

      Comment

      • tom66
        EVs Rule
        • Apr 2011
        • 32560
        • UK

        #4
        Re: Copper pads on printed circuit board came off.

        You need to get a more in focus and closer picture, we need to be able to trace it through. Maybe you will have to remove some of those green caps to get access.
        Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
        For service manual, schematic, boardview (board view), datasheet, cad - use our search.

        Comment

        • topfli8979
          Badcaps Veteran
          • Oct 2012
          • 311
          • USA

          #5
          Re: Copper pads on printed circuit board came off.

          sorry ffor delay, been out of town. Here is a closer more focused picture.
          Attached Files

          Comment

          • mariushm
            Badcaps Legend
            • May 2011
            • 3799

            #6
            Re: Copper pads on printed circuit board came off.

            The trace goes from R5082 (the one below the text saying q5006 or q5008) to the hole .. carefully scrape off the insulation on that trace.
            Get some thin wire, lay it over the trace so that one end is almost near the resistor solder, and the other side goes down into the hole. When you put the mosfet or whatver that was on the heatsink, its lead will press against the wire and will make good contact.
            Now solder the wire and lead together and the wire to the wide trace (if you want, add a bit of solder to the resistor side and then solder the wire to that solder)

            Comment

            • topfli8979
              Badcaps Veteran
              • Oct 2012
              • 311
              • USA

              #7
              Re: Copper pads on printed circuit board came off.

              Ok, what about the other hole on opposite side of the FET, or does it all trace back to one source.
              Last edited by topfli8979; 02-16-2013, 10:33 PM.

              Comment

              • mariushm
                Badcaps Legend
                • May 2011
                • 3799

                #8
                Re: Copper pads on printed circuit board came off.

                Well, no offense but are you blind or unable to check? I can't see better than you from here.

                I've explained how the first one works, follow the process the same way for the other.
                Look around the hole for lighter green stuff, that's the copper trace under the insulation. Scrape that off and repeat.

                Comment

                • topfli8979
                  Badcaps Veteran
                  • Oct 2012
                  • 311
                  • USA

                  #9
                  Re: Copper pads on printed circuit board came off.

                  That is why i was asking if it is possible for both sides to come off one source, the opposite side does not have a lighter green trace.

                  Comment

                  • mariushm
                    Badcaps Legend
                    • May 2011
                    • 3799

                    #10
                    Re: Copper pads on printed circuit board came off.

                    Yes, it does have one.

                    All three holes have something, if not on the top, on the backside.

                    On the far right hole, there is something that looks like a trace going diagonally towards the corner of that white rectangle. I may be wrong and it could be just a reflection.

                    The center hole's trace may be going behind the heatsink under that thick white bar, or both center and right hole's traces may be on the other side of the board.

                    Just get some flashlight or some desk lamp and shine the light through the board and you'll see the traces, if you can't see them with your eyes alone.

                    Comment

                    Related Topics

                    Collapse

                    • Alimash
                      op amp circuit function?
                      by Alimash
                      Hi,
                      I am repairing a ups which doesn't turn on ,it has the following ICs:
                      SG3525 used to drive inverter mosfets.
                      couple of uc3483, one for the power supply and another to drive a big mosfet at the output stage(i think the technique is called boost)
                      A LM358 and TL074 for control mechanism and of course the uController.

                      The SG3525 is shutting down every time the ups is turned on.
                      I want your help to know the function of LM358 and TL074 in the system.
                      I reverse engineered the LM358 circuit and i think that one of the block(A) is used for battery level...
                      Today, 07:45 AM
                    • Ancient1
                      MacBook Pro 2012 A1398 : Battery BMS circuit repair OR can it boot WITHOUT a battery ?
                      by Ancient1
                      Hi
                      I received such Laptop as junk. Opening it I saw a lot of whitish water residue , but no corrosion really ( few coils have small brown rust marks, no green copper ).
                      I cleaned all thoroughly and interestingly , its the Battery BMS board that has the real corrosion spots.. under the protective clear Goo !!

                      I want to try and power up the laptop

                      Battery is swollen. But I don't want to buy a new battery right now , of course .

                      I started work on the BMS by zooming in on green spots . 2 VIAs are filled with rusted copper goo - who knows...
                      04-17-2024, 12:46 AM
                    • Astonished
                      Fixing the Charge Circuit of the Batteries of the DC Motor
                      by Astonished
                      Hi friends of electronics

                      What you see in the video and pictures attached is the circuit for charging the batteries of a DC motor.

                      The problem is that this circuit cannot charge the batteries (3 1800mAH NiMH batteries) any more. When the circuit was OK, its green LEDs lit up one at a time to show that the batteries have charged more. But now that the circuit is flawed, LEDs light up as you see in the video and at the same time successive beeps are heard.

                      Please help me fix this circuit.

                      (the datasheet of the IC: https://pdf.datasheet.live/28...
                      01-28-2025, 06:24 AM
                    • rddube
                      Lenovo L490 Ram voltage circuit malfunction
                      by rddube
                      Hello friends,

                      Looking for some guidance here. The RAM voltage circuit on this motherboard keeps burning out PU301 which is a RT8231AGQW. Copy of the board with the burnt chip attached with some voltage measurements and copy of the schematics also included.

                      I think I've checked almost every component in the circuit, but when I change the RT8231, the laptop starts I have 1.2V on the inductor for about 10 seconds and then the RT8231 goes south and no more voltage on the inductor. All other voltages on the laptop are good, this is the only one conking out for a reason I...
                      07-15-2025, 04:41 PM
                    • Tarot Superstars
                      Short Circuit tester
                      by Tarot Superstars
                      Hello.
                      I have seen a short circuit tester made with 3 * 9V batteries, a voltage limiter component and a resistor connected to the probes of a multimeter.
                      The theory is that the meter becomes sensitive enough to read very low resistances and the lowest resistance to ground on a circuit is likely to be a short circuit in that area.

                      Link
                      The Amazing $1 Short Finder Upgraded! Convert ... - YouTube
                      https://www.youtube.com/watch?v=0eixDdCpiO4

                      My multimeter isn't normally sensitive to very small resistance, but when I put a 1 mega ohm resistor...
                      09-25-2023, 09:11 AM
                    • Loading...
                    • No more items.
                    Working...