I have been working on a project for a while now and today I came up against a problem where I screwed up, I missed a few very necessary components off my schematic.
The initial board outline is 157*80 and getting on for 800 components was already super tight, the missing components mean there is now no chance thee additions will fit.
So the string question…
I am on a 6 layer board and decided to look at double sided assembly,
My options seem to be double sided, larger board or a second board on top.
Are there any ‘rules of thumb’ on cost multiplication here, Ie is Double sided so expensive that a second board is cheaper?
I looked at jlcpcb etc but they want a gerber for a PCBA quote and I am not that far along…
I know the most cost effective solution is make it bigger but that comes with a whole host of other issues.
I point out that often you will have footprints which lend themselves to placement on the back side. I recently did a board where I had only two components on the back side, only because it seemed to make the most sense. I wanted an RC lowpass to be connected relatively close to my fine pitch SMT IC, and I did not want to move other more-critically-placed footprints out of the way in order to do that.
The best example (was not quite my situation) that I can think of is where you have a 14 pin DIP IC, and you have one or two passive components connected between pin 3 and pin 10. Placement of those footprints on the backside allows reduction of track length as compared to the other options.
The title was indicative of my question thought process but you are right of course, I have adjusted.
As it happens, I have now managed a redesign after being able to reduce courtyards to what JLC are still more than happy with. My next issue is copper balance but that’s a whole other story!
The learning Journey is fun, if a little daunting, this and other forums have been very good.
