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Schmartboard review

As one of the winners in the Circuit Cellar contest, I was offered a sample Schmartboard to try out. While I'm known as that guy that uses those insanely small parts, I accepted the offer to see what they're like.

The board came with an Analog Devices AD8608, a quad op-amp. The Schmartboard is designed such that the copper pads are both lower than the surrounding resist, and pre-tinned with sufficient solder. This is supposed to make it trivial for the user to position the chip and solder it. My first task (besides fiddling with it :) was to measure the depth of the channel the leads go in. I had a heck of a time doing this, as the chip just didn't want to be positioned between the pads - it kept falling into the slots. Eventually I was able to hold it steady enough to measure the thickness of the board with the chip in the slots and between the slots. In: 0.072 inch, out: 0.075 inch. Thus, the slots are 0.004 inch deep. Given that the leads are only 0.009 inch thick, this is almost half the thickness of the leads.

The slots are about 0.375 inch long, giving ample access in this sample board. While this is not neccessarily representative of all other schmartboards, from the diagrams of them it does seem that they have such access as well.

The sample even came with the little bit of masking tape needed to hold the chip in place on one side while you soldered the other side.

Ok, now for the important test... soldering. Yup, seems to do what they say. I used my 0.020 inch tip, which is a little small, but as long as I went slow enough to heat up the solder, when the tip hit the chip leads the flux wetted it and the connection was made.

For fun I also soldered a 30 gauge wire wrap wire into the slot, which worked, but more solder would need to be added to make a mechanically sound connection.


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  Copyright 2008   by DJ Delorie     Updated Apr 2008