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Do high volume manufacturing outfits all make a custom made 'bed of nails'?

I have not been able to find a ready jtag contact pattern and spring loaded header other than tag-connect pointed in this answer.

Are there really no common JTAG PCB pattern and pogo-pin parts?

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    \$\begingroup\$ People that do it very likely have bed of nails testing implemented anyways already. \$\endgroup\$ – PlasmaHH Oct 21 '15 at 14:04
  • \$\begingroup\$ even then, shouldn't be a standard jig for the jtag part? \$\endgroup\$ – MandoMando Oct 21 '15 at 14:05
  • \$\begingroup\$ why? adding a few pins more is going to cost the same, no matter where you add them \$\endgroup\$ – PlasmaHH Oct 21 '15 at 14:13
  • \$\begingroup\$ Tag-connect, which you reference, is such a part - so there's clearly at least one. \$\endgroup\$ – Nick Johnson Oct 21 '15 at 14:34
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I've seen three approaches in the wild:

  1. If there is enough space on the board, the standard layout for that CPU type is used (e.g. 14 pin ARM, or 10 pin Altera) with a standard thru-hole connector, and the traces to the connector are routed on the top. For development boards, the header is populated normally, and in production, the holes aren't drilled, leaving large round pads.

  2. Companies that have a large number of different designs sometimes standardize internally, e.g. 1mm raster and a fixed distance from the board edge, so the same test jig can be reused.

  3. Fully custom solution for a board. If you produce a million units or have a very complex layout, it may simply be cheaper to make a custom board with pogo pins than to change the layout of the mass-produced board.

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  • \$\begingroup\$ Just to add to 3: If you are making a million units you are looking at automating the whole process which means you want some inline solution with an automated board handler based on a custom fixture that contacts the board and not someone manually plugging in a cable. \$\endgroup\$ – og1L Oct 24 '15 at 9:52
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Do high volume manufacturing outfits all make a custom made 'bed of nails'?

Yes. Usually there's a need to provide power and/or test some other items at the same time, and it's reasonably cheap to fit some more pogo pins to the bed. Most of the cost is the mechanical engineering of getting the board to locate and clamp correctly.

The other alternative is to put an edge connector on the PCB panel, allowing you to program all the units before de-panelisation.

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