I have a question about Schmartboards. It looks like the through holes on their QFP adapters are on a staggered 0.050" grid but there are no dimensions on their drawings. Is that true? Also, there are some rectangular pads near the chip area that appear to be for installing 0.050 pitch surface mount connectors or headers. Any ideas about that?
It looks like the through holes on their QFP adapters are on a staggered 0.050" grid but there are no dimensions on their drawings. Is that true?
Yes - those holes accept parts like Arduino female headers.
Also, there are some rectangular pads near the chip area that appear to be for installing 0.050 pitch surface mount connectors or headers. Any ideas about that?
Hmm - maybe surface mount headers? Probe points?
http://www.schmartboard.com/schmartboard_pd_202-0011-01.pdf Yes, no dimension. Adjacent holes are 0.1" apart.
5 sets of pads in each corner too for surface mount to thruhole, maybe install parts there & jumper over to pins?
Looks like outer two rows will allow two 2x6 headers (2x12 total) to be used without having the holes be offset by 0.05", or a 2x13 with the left-end set of holes being the same signal
Also, there are some rectangular pads near the chip area that appear to be for installing 0.050 pitch surface mount connectors or headers. Any ideas about that?
Hmm - maybe surface mount headers? Probe points?
They remind me of what these Samtec headers are designed for. I've ordered some Schmartboards and I'm about to hit Samtec up for some "sudden samples". I'll report back what I find.
After getting the headers and some boards to try them with, I'm going with your suggestion that they are probing pads. They have the right pitch but a header would have to be unusually slim to fit.