DIP switch replacement

Question

I'm working on a board where I will need to mechanically enable/disable some functionality/portions of the hardware.  I would like to have the functionality of a DIP switch (see below) but it feels so 1980s.

It seems out of place next to all my ultra-miniature leadless package parts.  Has anyone come across anything more "modern" looking and that won't require me to use a fine-tipped pen to switch?

Additional Info

The switches are for an in-house test board (meant only for internal engineers)
I (the people paying me) would prefer it to cost as little as possible (so there is no time for me to implement any software solutions)
The switches will be infrequently changed from states (some only a few times in their life)
Size is a moderate concern.  If it is too big it will look awkward next to all my small parts (and possibly make my board top-heavy)

Oli Glaser · Answer

I think the solder bridge will probably work fine if they are not changed that often.

However, I think the DIP switch would be the easiest and most reliable option. Just in case you weren't aware there are SM DIP switches available that are not too "1980's" (IMHO) and don't take up too much room:

The 8-way one shown above is from this page, it's ~11mm long and not too pricy at £0.96 for one.

Kevin Vermeer · Answer

Because your board will be used by internal engineers and infrequently changed, I suggest a solder-based or track-cutting solution.

A pair of pads on your PCB make a fine switch, and there's nothing that could be cheaper.  Touch it with your soldering iron and some solder, and you've made a connection.  Touch it with the iron and some braid and you've disconnected it.

If you want it to default to 'on' and you're using stencil + reflow soldering, just add some paste over the whole area and it will short during reflow.

Sparkfun's library has a few examples, they look like this:

They can be quite small; an 0402 resistor footprint works fine for this purpose and takes up far less space on your PCB than a DIP switch.

DIP switch replacement

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