New User - Board trace design specification question

June 23, 2016, 12:34:06 am

I am an undergrad college student who, within the past day, has started learning how to model PCBs (specifically with Diptrace). I know the questions following may be answered in the "about" page, however the terminology there is not familiar to me. I simple would like to know what the minimum trace width is, the minimum spacing(between components and traces), the minimum clearance from traces to the edge of the board, minimum drill size, and minimum annular ring. If someone can inform me on all/most of these it would be much appreciated!

Re: New User - Board trace design specification question

Reply #1 – June 23, 2016, 01:22:59 pm

> I simple would like to know what the minimum trace width is, the minimum spacing

Min w/s 5/5mil(O/L)
(w = width, s = space, O/L = Outer Layer I think)

But personally I wouldn't go under 6/6.

> the minimum clearance from traces to the edge of the board,

I think the same as above, but I would always use more, about 0.5 to 1mm border if I can, although I have the DRC set to 12mil (0.3mm) and have had DirtyPCBs produce boards with that no issues at all. I'm just conservative if I can be.

> minimum drill size

Min diameter of finished hole 12mil (0.3mm)

> minimum annular ring.

In theory the drill position accuracy is 2mil, so even 5 mil would be ok without risk of blowing out, I effectively use 6 mil for teeny vias and it works fine so far.

For what it's worth, here are the DipTrace DRC settings I used last with DirtyPCBs: http://imgur.com/a/k6OnG

Note that I have the DRC set to 8 mil minimum width, probably on the very conservative side, but by the same token, more copper more better.

Re: New User - Board trace design specification question

Reply #2 – June 23, 2016, 03:23:09 pm

Thanks for the reply, this is very helpful!