Screaming Circuits: DB25 - Survey Says...


DB25 - Survey Says...

DB25 with 
issuesI've gotten a number of answers to my question: "What's wrong with this picture?" All good responses.

  • Via between the connector pins
  • Soldermask covering the pads
  • Tight zig zag on some traces
  • Traces real close to some of the pads
  • Uncovered/partially covered via in between the pads
  • No clear pin one markation
  • Tear dropped pads might be helpful

The biggest problem that I see in terms of buildability is the solder mask on the pads. Yes, we can make it work. In a prototype world, we make a lot of stuff work that by all rights should not, but once into production, or for best reliability, that mask is a problem.

The tight spacing between some of the traces and the pads is not inherently a problem, but based on the mask issues and the poor drill alignment in the via, I'm lead to question the workmanship on this PCB to the point that I would be concerned about anything too close to anything else on this board.

DB25 with issues del The third concern that I noted, I'm no longer quite sure of. I just have the photo in hand, not the actual PCB. When I first looked at this photo, I interpreted the lighter area around some of the pads as delamination. We see that sometimes and it's a bad problem. With a second look though, I'm not so sure that I'm not just seeing an inner copper layer with openings around most of the pads. Hard to say just by the photo.

I'm not terribly concerned by the lack of pin one designator. This is the solder-side of the board and as long as this connector is on the correct side of the board, it's not reversible. The via doesn't bother me much either, as long as the connector doesn't have any exposed metal over that side. Most of these would have plastic down there now.

Duane Benson


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