For a typical protoboard like this one

about how high does the voltage need to get across two neighboring pads before they spark across?

I am afraid of connecting my 20V power supply across two neighboring pads for fear of discharge but I can't find any info on the protoboard's datasheet.

Thanks

 

I wouldn't worry about +/-20 rails. I've never had a problem.

 

I agree that 20V is no concern. I'd begin to wonder at maybe 100V or more.

 

Here's some info.

 

My boards have a pad spacing of 0.1", and adjacent pads come within ~0.9mm (0.036") of each other (0.036"). According to the reference provided by above by @crutschow, that allows for a voltage difference of >150V, maybe up to 160V or so.

That's plenty for most stuff but it does tell me that rectified AC at ~170V would not be a good idea. That fits my hunch that getting over 100V warrants looking into the details.

 

K cool, thanks everyone!

Sorry for late reply

 

My boards have a pad spacing of 0.1", and adjacent pads come within ~0.9mm (0.036") of each other (0.036"). According to the reference provided by above by @crutschow, that allows for a voltage difference of >150V, maybe up to 160V or so.

That's plenty for most stuff but it does tell me that rectified AC at ~170V would not be a good idea. That fits my hunch that getting over 100V warrants looking into the details.

What you are assuming is the voltage is across two adjacent pads.

If you skip a row you get not 150 V but 300 volt iolation, and you can keep skipping rows till your sleep at night remains undisturbed.

 

Yeah, putting even 12V onto two adjacent pads makes me nervous. It's so easy to get a whisker of solder or a bent component lead or whatever. Those don't really seem to happen but I prefer not temp fate.