And Another Reason...
Another reason to inspect your PCBs before sending them on to the assembly house.
At first glance, these boards looked fine. But with a little closer inspection, you can see that the middle barrel isn't plated through. Bummer.
There are a number of possible causes for this.
- It could simply have been a goof at the board house. Sometimes a process will slip or someone in CAM will introduce an error.
- It could have been caused by improperly creating a library part. Maybe the symbol was built up by hand and ended up with a non-plated hole in that spot.
- It could have been built without a library part. Sometimes designers will just create a place for a thru-hole part using vias and traces instead of creating the library part. If that's the case, the center could have ended up with a non-plated hole instead of a plated via.
Myself, I'm betting this was a board fab problem. In any case - another good reason to check out those boards before sending them on for assembly.
And even better then just looking at them - also have them electrical tested at the fab house. Our fab partners at Sunstone Circuits can do that for you.
Roll out the barrel...
and have a barrel of open solder joints