PCB Manufacturing
It's never been more affordable to have PCBs professionally made. Be thankful and take advantage of it!
PCB manufacturing -- even of prototypes -- isn't a business you really want to be in. It's very labour intensive, requires reasonably expensive equipment to produce repeatable results that correspond to modern fine-pitch parts, and involves a number of chemical processes. Unless you are doing RF design that requires a lot of quick iterations to get an efficient layout, it just isn't worth bringing PCB manufacturing in house. It generally isn't even realistic if you aren't basing a business around it (and your competition will be tough if you are). You can get high-quality, professionally made PCBs with solder mask and silk-screen for under 100€. Some companies targetting low-volume prototypes will even throw in free laser cut stencils, making the deal particularly attractive since professionally made stencils typically approach the same price as PCBs in very low quantites.
In any case, whether you do the assembly in house or outsource it, the burden will likely fall on you to have the PCBs made. You probably want to resist the temptation to delegate this to the assembly house if you are outsourcing, since you likely want to have complete control over the PCB specifications (if this is important with your product). In our case, we principally use two main PCB manufacturers depending on our requirements:
PCB Pool (Ireland)
We usually use PCB Pool (based in Ireland) for situations where we only need one or two prototypes, with a typical price tag a bit under 100€ with silk-screen. The cost per board is slightly higher than in China, but a significant advantage with PCB Pool is that the include a free, high-quality laser-cut stencil with every prototype PCB (you simply need to ask for it), which in our mind cuts the price in half since we'd need to have one made for 50-60€ anyway. Sometimes, just before production we actually order one last prototype from PCB Pool just to have the stencil and test the final PCB layout. The stencil can then be carried over to the production boards if everything is OK.
Technical Restrictions
- Minimum Trace/Spacing: 8mil (0.2mm)
- Minimum Annular Ring: 12mil (0.3mm)
- Minimum Drill: 0.4mm (16mil)
Hole Tolerances
- +/- 0.1mm for PTH holes
- +/- 0.075mm for NPTH holes
If you are using Eagle, a
design rules check file can be downloaded from the PCB Pool website. This files allows you the check if your design meets the minimum technical requirements. If it doesn't past this test, it probably can't be manufactured without added expense.
PCB Cart (China)
For larger prototype runs (more than 5-6 copies of a design) and for final production runs we usually use PCB Cart in China. They offer very competitive prices, and allow a number of different configuration options such as different ROHS-compliant finishes, solder mask colours, minimum trace and annular ring widths, etc. While there are many alternatives to chose from, we've had a good experience so far with PCB Cart (~30 orders so far), and they offer quick online pricing. There are upfront tooling fees to pay (that vary with your technical requirements), but you only need to pay these fees once (usually around 50€ or so). If you reorder a previously manufactured board, you only pay the per-board cost which is general about 1/2 the initial order price.
We've published a number of Design Rules files for Eagle to match PCB Cart's offerings. You can find the files and bit more information about PCB Cart in this blog entry: Eagle Design Rules Check (DRU) for PCBCart.