I currently have a 2 layer FR4 board that is basically a microcontroller with a motor attached to it. There are some discrete switches and connectors as well.
Most of the components are SMT components (0805 being the smallest). There are some through hole LEDs and connectors.
For a single layer (one side) board would I have to replace my SMT components to through hole ?
For a single layer (one side) board would a decent board house still be able to do 10 mil traces or are there new rules for single layer boards ? ( I understand that I should contact the board house directly to find out their capabilities)
Any other useful gotchas (or questions I have failed to ask) would be appreciated from your own experience when doing a conversio, design or increasing manufacturing yield.
Best Answer
I've designed around 8 or so single sided mixed SMD/through hole PCBs (most with microcontrollers, one with some radio modules, and a couple with a low speed gate drive).
If you're doing anything that requires a really good ground plane you should probably stick with the two layer board at a minimum. Expect to put a lot of effort into getting your ground planes to be continuous with a single plane of copper. I've heard it said that single sided designs without jumpers are a kind of holy grail for PCB design. The ratsnest on your pcb design tool is actually a very good indicator whether or not your design will be easy to route on one side. Part layout and grounding will be your most difficult challenge with these designs. You'll want to actually trace out the likely path your ground currents will take (or use something like Hyperlynx PI if you have access to that kind of tool).
That said, I've successfully mixed through hole and smd components to give myself a two sided board with one layer of copper (through hole on top, smd on solder side). These board were all milled rather than etched and didn't have any solder mask. In fact, I tried my hardest to only go with single sided boards because the people who operated the milling service I was using were not so great at aligning the two sides (and the through holes weren't plated). I guess that's the price to pay for $0.07 per in^2. If you're going with a standard board house, their two sided rules (trace width, hole size, etc) should apply all the same. From their perspective, a single sided board should be the same as a double sided board unless they're doing something wonky.