I farmed-out PCB board fabrication to an off-shore commercial board manufaturer. I supplied these parameters during the board manufacturing process:
| Parameter | Value |
|---|---|
| Material | FR-4 TG150 |
| Size | 108 x 63.5 mm |
| Layers | 4 |
| Thickness | 1.6 mm |
| Min Track/Spacing | 8/8mil |
| Min Hole Size | 0.3 mm |
| Solder Mask | Blue |
| Silkscreen | White |
| Surface Finish | ENIG - Immersion gold 1U" |
| Via Process | Tenting vias |
| Finished Copper (outer layers) | 2 oz Cu |
| Inner Copper | 1 oz Cu |
| Gold Fingers | No |
| "HASL"to"ENIG" | No |
The PCB shop I ordered from also will create stanless steel solder masks for a board, which I ordered at the same time. Given the small footprint of the TI LED driver ICs, this made laying down the solder for the reflow process much more reliable.
I used a reflow oven to solder components to the boards. I expect it would be difficult to hand solder the TI ICs.
I populated the front (component) side of the board first using Pb 63/Sn 37 solder paste. I used low-temperature Bi/Sn solder for the back (LED) side. This allowed me to used a lower temperature reflow profile for the back -- insuring the front components remained in-place during the reflow of the second side.