Emboldened by my past success with the Roomba revision D boards, I decided to incorporate this new knowledge of reflow into the next revision for the keyboard toy. A few things needed to change with this design. First, I never did find a good way to incorporate the port expander into the final design; so out it went. Second, the wire harness proved much too cumbersome–I would use a simple female header instead for the TFT. Third, to save space, I would use the TQFP-32 package for the ATMega328p. Continue reading Reflow soldering: further experiments and observations→
While trying to iron out the last details of the keyboard project, I decided to try my hand at a surface mounted design, and ordered some tiny ATTiny45 chips (TSSOP) while ordering some other things. What caused me to take the plunge was that I realized I actually had all the tools I needed already. Reading up on the topic lead me to the conclusion that the most economical way to do the soldering would be to use a skillet or hot plate; and rather than buy another tool, I wanted to attempt to use a cast iron skillet that I already had. My thought was that cast iron heats very slowly and evenly and would have many of the same benefits, in that respect, or some other options I had read about. Continue reading Adventures in SMD→
