What are Lifted Pads on Printed Circuit Boards?

What are Lifted Pads on a PCB? What causes them? How can you fix this?

PCB Repair Solder Soldering 
1 Answer
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Editorial Team - PCB Directory

May 22, 2021

A lifted pad on a printed circuit board is a pad that detached from the surface of a PCB. This results in an improper connection to the lead or component causing the PCB board to malfunction or not work. This defect is usually found on single-side PCBs that use a thin copper layer with no through-hole plating. It is caused by excess heat and/or excessive force on the solder joint. The lifted pad issue can occur in both through-hole and surface mount connections.

What causes a Lifted pad in a PCB?

In the wave soldering process, the surface of the PCB tends to heat up. This can reduce the adhesion of copper and therefore result in a lifted pad if the PCB is handled roughly or mishandled. So, it is important to handle the printed circuit boards carefully when taking them off the conveyor belt after soldering.

Another thing that can cause a lifted pad is using a hot soldering iron for the de-soldering or rework of components. Again, the principle is the same, heating of the board can reduce adhesion of copper. So once the repair/rework process is complete and the board not handled carefully before the connections set in, a pad can lift.

How to avoid PCB pad lifting?

The best way to avoid lifted PCB pads is to handle the board carefully after the soldering process till the solder has solidified properly.

How do you repair a lifted pad in Through-hole PCBs?

Lifted PCB Pad Repair in Through-hole PCBs

The good thing is that this defect can be repaired in most cases. In the case of through-hole PCBs, if the board has a solder mask, scrape off enough of it to expose the copper trace where the solder connection usually takes place. Then insert the component lead in to the hole and bend it to touch the copper trace where the pad is lifted. This then needs to be soldered to make the electrical connection.

How do you repaid a lifted pad in Surface mount PCBs?

Stepwise explanation:

  1. Clean the lifted pad area.
  2. Remove the lifted pad.
  3. Remove any epoxy residue or contaminants from the surface of the board and clean the area.
  4. Scrape off any solder mask from the connecting circuit and clean the area.  
  5. Apply a small amount of liquid flux on the connection surface of the board and then clean the area.
  6. Select a new appropriate pad that matches the pad that needs to be replaced.
  7. Use a small amount of epoxy (after mix) on the repairing surface.
  8. Then, place the new pad on the board by using a high-temperature tape.
  9. Cure the epoxy.
  10. After the curing process, remove the high-temperature tape used for pad alignment purposes.
  11. Use a little liquid flux at the solder joint of the new pad.
  12. Mix epoxy and coat the new solder joint connection. Finally, if required, apply a surface coating.

If you have a PCB with a lifted pad, you can always approach a company to help you resolve this. Click here to see a list of PCB repair/rework companies.

You can also get a quote of your PCB Repair requirement from multiple companies. Try out our PCB Repair Quotation Tool.

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