So this is my first post so please forgive me but inform me if I'm breaking any forum rules.

I'm trying to layout a through hole HDMI connector in Eagle. The issue I'm running into is that the gap between the trace and the pads it passes between is too narrow. If you have any tips or suggestions of things to try that would be so helpful.


Here is a link to the part drawing: https://www.amphenolcanada.com/ProductSearch/drawings/AC/MHDRA111XX.pdf

  • \$\begingroup\$ What design rules (minimum trace width, minimum gap, minimum annular ring) are you using? You may need to use tighter rules (and pay a bit more for the PCB) when you use fine pitch parts. \$\endgroup\$ – Spehro Pefhany Apr 12 '18 at 15:41

The pitch is 1.5mm and the recommended hole diameter is 0.65mm, giving you 0.85mm for two annular rings and one trace width plus two spaces. Using 0.15mm for track and space, and 0.2mm for annular ring will work.

Those are not particularly challenging rules for PCB makers with modern equipment, particularly if you only push it to the limit in a few places (like where the tracks escape from the middle row of the connector.

So that would be a pad diameter of 1.05mm (0.65 hole + 2 annular rings of 0.2mm).

  • \$\begingroup\$ Thanks for your answer. The design rules I'm using are 8 mil clearance, and 8 mil minimum trace width. Do I need to go smaller? \$\endgroup\$ – K Costner Apr 12 '18 at 15:53
  • \$\begingroup\$ 8 mil is 0.2032mm so you would need annular ring of 0.12mm, (4.7 mils) which is very undesirable and unlikely to be paired with relatively coarse 8 mil capability. So, I would say yes. Do check the annular ring capability of the supplier(s) you have in mind. Don't be afraid to adjust the pads that don't have to be that small to be bigger to make it more easily manufactured, assuming you are diligent with DRC there is no risk. \$\endgroup\$ – Spehro Pefhany Apr 12 '18 at 16:05
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    \$\begingroup\$ Okay so say I can get 6 mil traces and annular rings. That should leave enough room for almost 8 mils of clearance between the pad and the trace, yes? I'll check with my supplier to see how narrow they can go. Thanks again! This has helped a lot. \$\endgroup\$ – K Costner Apr 12 '18 at 16:30

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