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I am trying to build a footprint for a Samtec HLE-125-2-G-DV-LC, which is a low profile SMT socket for dual row, .1" center square posts. The "LC" indicates that the socket has a pair of Locking Clips - and those require a 47 mil hole for each to be pressed into. These are part of the body of the connector, not electrical pins. I've had some puzzling problems trying, with Pad Stack Designer, to create these holes.
1. I used the same techniques as in the RJ45 video, and created a round through-hole, with no pad. PSD then created pads on the Top and Bottom layers, with sizes that were about half the hole size. Specifically, a 47 mil hole got 24 mil pads on Top and Bottom, despite selecting "None" in the Shape. This, of course, causes the build to fail with dire warnings about pads being smaller than the drilled out hole... and entering a size of "0" for the Pad X value just gets it re-set to 49 when I leave that edit-box.
So, I just "Add" the new pad stack and go back to the Pad Stack Manager.
2. In the PSM dialog box, I select the newly formed pad stack, and then work in the bottom area of the dialog box, labelled "Pad Stack". I see that the PSD, despite being instructed not to create a pad, has created pads on Top, Bottom, and Inner, as well as Top Mask, Bottom Mask, and Keepout All. These are visible on the "Pads" tab. I delete every entry except the "Keepout All", and adjust its size to match my needs in the edit box to the right. Moving to the Hole tab, I find that the hole is listed as a slot, rather than a "round", so I change that. Clicking "Done" (lower left) creates a new pad stack name - using metric values, despite my selecting mils. I click the upper "Done" (upper right), agree that I want to save my changes, and go back to the footprint.
3. I then place two pins, calling out the new pad stack, and using pin numbers larger than the 50 real, electrical pins on the part, 51 & 52. The holes appear as expected... but they both still have the pads in the pad stack, despite having deleted them in the PSM.
I don't really want two "pins" - Allegro requires a footprint to have as many pins as the schematic symbol, which of course doesn't include mounting holes.
I REALLY don't want pads, of any size, to appear on Top, Bottom, or any Inner layers. If they MUST appear, then they should be some size that doesn't blow up the Build of the part, because they will be drilled out.
Oh, and I saved the part to an FPX library. Then I closed PCBLX, re-opened it, and loaded the new library, and tried to build the part. PCBLX crashed with NullReference exceptions. It's repeatable. If I don't delete the unwanted layers in the hole's pad-stack, other NullReference errors are thrown when I try to examine the part from the library (before I can even try to build it).
I'm using 2014-9. Outputs using the OrCAD PCB (V16.6) translator. The FPX containing the problem part is attached: uploads/8170/Samtec_HLE_50pin_SMT_with_mounting_holes.fpx" rel="nofollow - uploads/8170/Samtec_HLE_50pin_SMT_with_mounting_holes.fpx
I've tried to start over - same results. There must be some magic that I haven't figured out yet... This has been a great tool, and the addition of POD & STEP models was a big help. My intuition is just failing me this time... Any help would be greatly appreciated!
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