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I am designing a small (30mmX20mm) and not complicated two layer PCB. It is possible to do the design without using vias.

  • Is it possible to determine how much can I save approximately by eliminating vias from design?
  • Is it worth it?
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    \$\begingroup\$ Speak with your PCB supplier. \$\endgroup\$
    – Andy aka
    Apr 27 '20 at 17:13
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    \$\begingroup\$ Those were old school cost adders. No one asks for that information anymore. ie. It's not a significant cost driver. \$\endgroup\$
    – Aaron
    Apr 27 '20 at 17:19
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    \$\begingroup\$ Not worth it. Just having vias saves you SO MUCH EFFORT in hand assembly and layout. You would save more money doing practically any other cost cutting measure. \$\endgroup\$
    – DKNguyen
    Apr 27 '20 at 18:21
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    \$\begingroup\$ While the cost per via is negligible nowadays, the cost advantage of completely eliminating the drilling operation might actually be considerable, even for a low volume project. Only your PCB supplier can give you the actual value, though. (And I agree with DKNguyen it's likely not enough to offset additional assembly costs). \$\endgroup\$
    – The Photon
    Apr 27 '20 at 18:32
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    \$\begingroup\$ No TH components and no vias = single layer board -> Cheaper than 2 layers. \$\endgroup\$
    – Lior Bilia
    Apr 27 '20 at 20:32
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Basically, the cost breakdown for doing the drilling of vias and other through-holes is:

  • (1) setup time (putting the board on the machine)
  • (2) time on the machine
  • (3) removing the board from the machine
  • (4) (later) plate-through holes

Costs #1, 3, and 4 are the same regardless of the number of vias. Cost #2 does vary, not just with the number of vias, but how long it takes to drill them, and how often the bit needs changing.

So there is some benefit to reducing vias if you have to have them, and also keeping the hole sizes large enough that the bits don't wear out as quickly. But in the big picture, for a very simple board this won't matter much.

Also consider that if your board has a special shape or uses 'mouse bites' or other breakaways for panelization, that takes routing time on the same machine that does the drilling. This in fact will dominate time spent on the drilling table. Using v-scribe singulation avoids this.

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Centuries ago, when I first started designing PC boards, I believe we were charged for the number of vias/holes (or number of different hole sizes) on a board, but that charge was dropped long ago.

There may be an extra charge if you have an excessive number of holes - like for a board matching the hole pattern of a plastic breadboard - but there is not usually a per-hole charge for "normal" PC boards. (However, this may depend on the board shop..)

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    \$\begingroup\$ It is a little joke. It probably feels like a very long time ago. \$\endgroup\$
    – Robyn
    Apr 28 '20 at 7:45
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    \$\begingroup\$ Centuries ago the cost of vias was higher. Replacing drill bits is relatively cheap, but having to re-string your bow due to wear and tear while drilling... that's expensive! \$\endgroup\$
    – Cort Ammon
    Apr 28 '20 at 18:49
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It is not worth it, unless you make million or more units per year. The cost per via on a 2 layer board, assuming no HDI, laser drilling, back filling or similar high cost requirement is negligible (less than 0.001USD).

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We've been involved in high volume, consumer electronics, and produced mostly overseas in 50k quantities of product runs. And the answer is that we've never seen it presented as a cost driver. I wouldn't be shy with the vias from a design perspective vs. cost analysis.

As others have said, the layers of the board and size of finished board are the biggest drivers.

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For small orders, it is likely that your board design will be put on a panel with other customers' designs, and if those people use vias, the panel will be put into the via drilling machine nonetheless, so there is no cost difference other than machine time, which is really cheap.

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