Electronic – Acrylic mounting and esd


I like the aesthetic of clear acrylic mounting of PCBs and I want to use it for a project I'm working on. For example as seen in the Mighty Ohm Geiger Counter,

mighty ohm case

Is esd something I should worry about? The project like the Geiger counter above will be handheld for use.

Also somewhat related, is it safe to use plain old rubber foam as padding with regards to esd (where the rubber foam would be in direct contact with traces and maybe some components on the PCB)? And what about as a substitute for rubber bumpers?

Best Answer

ESD should always be a concern with sensitive devices. I've seen plenty of uControllers act seemingly normal but have peculiar behavior, in the end to find it was ESD damage.

Typically transient suppression devices (aka tranzorbs) are put on signals that come in from a connector (especially communication signals, not power).

It's good that you're thinking about static from the foam and the acrylic.

Typically you will receive PCBs in a esd static free foam like this. Or more commonly within an esd bag.

I don't think the acrylic will be much of a problem. Although I do believe it retains a charge sort of like a balloon, so as long as the potential isn't enough to bridge the air gap to a trace/pin, it should be okay. Similar deal with plastic.. And we've all seen plenty of devices in plastic. (You would have to try really hard to do this, more likely you will absorb the charge on your person and discharge it elsewhere).