PCB Build
The PCB, layout was done manually using National Instrument's Ultiboard. The size of the board was exactly equal to the display at 79mm x 59mm.
3D CAD top view in Ultiboard
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PCB Layout in Ultiboard
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Remote PCB bottom showing pads for LCD display attachment
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Remote PCB Top
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A stainless steel stencil was used to apply lead-free solder paste using Beta-layout's magnetic workbench.
It was challenging to properly reflow solder the PCB, however, as .5mm and .65 mm pitch surface mount parts are included in the design. Hand soldering was not an option.
Using a modified, computer controlled, toaster oven purchased on eBay, the Atmega 2560, in particular, repeatedly had massive solder bridges that were very resistant to being fixed with flux and solder wick.
The initial PCBs were sourced from Beta-Layout's PCB pool service. By happenstance, a couple boards were ordered from Sunstone later. Under microscope, the Beta-Layout boards had no solder mask between the pads of .65mm and .5mm pitch parts. The Sunstone boards had complete solder mask even between .5mm parts.
It was challenging to properly reflow solder the PCB, however, as .5mm and .65 mm pitch surface mount parts are included in the design. Hand soldering was not an option.
Using a modified, computer controlled, toaster oven purchased on eBay, the Atmega 2560, in particular, repeatedly had massive solder bridges that were very resistant to being fixed with flux and solder wick.
The initial PCBs were sourced from Beta-Layout's PCB pool service. By happenstance, a couple boards were ordered from Sunstone later. Under microscope, the Beta-Layout boards had no solder mask between the pads of .65mm and .5mm pitch parts. The Sunstone boards had complete solder mask even between .5mm parts.
Beta-Layout .65mm part - no solder mask between pads
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Sunstone ,5 mm part - complete solder mask between pads
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It is not clear whether the two companies' processes are different for prototypes, or if the submitted Gerber files were processed differently. But reflowing the Sunstone board was done easily even with the computer controlled toaster oven, with only 1-2 total, minor, easily cleaned, solder bridges on the 2560 to deal with.
A complete microscope inspection of the board showed it was time to power up.
A complete microscope inspection of the board showed it was time to power up.