Contact Us

Use the form on the right to contact us.

You can edit the text in this area, and change where the contact form on the right submits to, by entering edit mode using the modes on the bottom right. 

Arch 12, Raymouth Road
London, England, SE16 2DB
United Kingdom

+44(0)7779606045

We create circuits that are both beautiful and functional
 

Blog

The art of routing: via fasteners

Saar Drimer

Someone over at the Electrical Engineering Stack Exchange asked about potential issues with 'via-in-pad' -- a via placed, well, in a pad. The advice is comprehensive, and the usual rule applies  -- it's fine when you know what you're doing and willing to pay for the "extravagance".

I chimed in with advice I got from a senior engineer looking over my shoulder whilst I was laying out a fairly complex board: place vias in pads for mechanical SMD interface components. Doing this adds strength on the z-axis of the board for otherwise easy to lift connectors. Take, for example, an SMD USB connector and the torque that applies from the cable casing; you could use all the strengthening you can get to prevent that sucker from lifting off the board with your tracks! It won't be enough for production -- for that you'd need something else to keep a connector in place or use a throughole connector, or both -- but it's great for kits, etc.

If I have space on the bottom layer I'd either just use a standard via, replicate the pad, or even oversize it on the bottom layer. I also try my best to have the same amount of vias in all pads so that they won't tombstone or create uneven connections. If you're going to use via fasteners and not solder by hand, you'll have to factor the vias into account since they may create an uneven pad, and will syphon out the paste, so you may need to add more.

I called these things 'via fasteners' since 'via rivets' was already "taken". Does this technique have a more established name? Searching for answers I found another StackExchange question about this same technique! More good advice and precautions there.