Printed circuit board assembly and solder validation method

A method for a printed circuit board (PCB) assembly having a first PCB and a second PCB, the first PCB having a first pin hole extending through the first PCB and the second PCB having a second pin hole extending through the second PCB, the PCBs being stacked over one another with the pin holes being aligned, the method comprising:

• providing a first electrically non-conductive ring entirely around the first pin hole, the first non-conductive ring being a portion of the first PCB;
• providing a second electrically non-conductive ring entirely around the second pin hole, the second non-conductive ring being a portion of the second PCB;
• providing a first electrically conductive trace, lacking a solder coating thereon, on a surface of the first PCB, the first trace having a first trace ring entirely around the first non-conductive ring with the first non-conductive ring being between the first pin hole and the first trace ring such that the first non-conductive ring electrically isolates the first pin hole from the first trace ring;
• providing a second electrically conductive trace, lacking a solder coating thereon, on a surface of the second PCB, the second trace having a second trace ring entirely around the second non-conductive ring with the second non-conductive ring being between the second pin hole and the second trace ring such that the second non-conductive ring electrically isolates the second pin hole from the second trace ring;
• inserting an electrically conductive pin, having a rectangular cross-section, through the pin holes with corners of the pin physically intersecting corresponding portions of the first non-conductive ring immediately adjacent to the first pin hole and the second non-conductive ring immediately adjacent to the second pin hole, the pin and the first trace ring being electrically isolated from one another by the first non-conductive portion and the pin and the second trace ring being electrically isolated from one another by the second non-conductive portion;
• after the pin is inserted through the pin holes, performing a soldering process intended to provide a soldered connection between the pin and the first trace ring and a soldered connection between the pin and the second trace ring, wherein a soldering connection is present between the pin and the first trace ring and a soldering connection is present between the pin and the second trace ring when the soldering process is successful, wherein a soldering connection is absent between the pin and at least one of the first trace ring and the second trace ring when the soldering process is unsuccessful;
• and
• detecting after the step of performing the soldering process intended to provide a soldered connection between the pin and the first trace ring and a soldered connection between the pin and the second trace ring that a soldered connection between the pin and at least one of the trace rings is absent when electrical continuity is absent between the trace rings as a soldered connection between the pin and the first trace ring and a soldered connection between the pin and the second trace ring have to be present to provide the electrical continuity between the trace rings due to at least one of the trace rings otherwise being electrically isolated from the pin by the corresponding non-conductive portion.