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I am trying to make a PCB footprint of a edge-mounted DE-15 D-sub connector (a.k.a. HD-15, DE15, HD15), however the datasheet does not seem to provide enough metrics to make it unambiguous.

Here is the datasheet:

DE-15 connector datasheet

This is my best try:

enter image description here

My two greatest issues is:

  1. The horizontal placement of the pins in relation to the screw holes. Currently I have assumed that the 0.45 mm measure denotes a horizontal offset from the midpoint between the screw holes, to the center of the middle pin on the first row (rounded up for connectors with an even amount of pins). Is this correct?
  2. The orientation of the connector. On the one hand, I could assume that the two bottom figures of the datasheet have consistent orientation with the cable being mounted from "above", and that the "PC Board layout" measure gives the minimum distance to other components. However, my first instinct was that the same measure gave the distance to the PCB edge, which should only be relevant if the cable is mounted from "below". In my footprint I assumed the former, but is it correct?

My guess is that there is a standard way to read D-sub datasheets which would make the footprint unambiguous, but I have not been able to find a resource for that.

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    \$\begingroup\$ For unknowns such as this, also obtain one of the connectors to compare against. Then you could confirm measurements with a micrometer, and find that the "PC Board Layout" would only work for the bottom side of the board. \$\endgroup\$
    – rdtsc
    Commented Aug 14, 2023 at 12:06

1 Answer 1

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For (1), You are correct in the offset of the centre line as 0.45mm. Then the top/bottom rows are aligned and the middle row pins are centred between the outer row pins.

For (2), the second diagram is bottom view of the connector. The lower diagram is top view of the PCB. That means your silk outline is mirrored - it should go downwards. Looking at the hole positions there is a mistake in the position of the left hand most hole - it should be on the top row with pin 1 not the bottom row.

Annotated diagram showing where pin 1 is

So the measurements of 11.43mm on middle and 10.43mm on lower are in the same direction - essentially indicating the connector is intended to be positioned with 1mm sitting off the edge of the PCB. This is probably a leftover from computer peripheral card standards.

It's not a brilliant dimensional diagram to be fair, not specifically labelling top/bottom view isn't helping. There is also one important dimension missing - how the 22mm and 11.43mm dimensions position in relation to each other, unless that dimension is in a different diagram somewhere.

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  • \$\begingroup\$ Excellent answer, thanks a lot! I do recall that I thought that the pin configuration must mean that the two diagrams are oriented consistently, so very nice catch that that is actually a datasheet error. These are all diagrams, so as for the 22mm and 11.43mm dimensions there definitely seems to be a dimension missing. \$\endgroup\$
    – JohanPI
    Commented Aug 14, 2023 at 9:53

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