Quote from: T3sl4co1l on Today at 07:33:58 AMSounds like one of those problems where the solution is worse than its cause -- the best way to avoid these is to do some component and connector choice,
No worries, i do not have a board routed, no set enclosure or components placed.
I do however have pre-selected a enclosure wich will fit everything nicely, but i would like to leave as much room as possible.
The idea is, a somewhat modular handheld unit for various projects with two boards.
The top board has everything on it, display, buttons, logic, power supply and storage.
The bottom board will be the "prototyping area" were the expansion board will be placed.
The 7mm board spaceing is governed by the internal case height, the bottom mounting pillars allready in the case, the board height and the spacing of the top board to the case face wich should be 3mm, the display is 2mm high and i would like a bit of room on top.
That leaves me with about 7mm between the boards:
The main goal is to make this fit with standard components, that includes standard thickness FR4, no modifications to the enclosure besides the cutouts for the buttons and display, trace with/spacing of 0.3mm and two layers only.
That way every board house can do these.
The display sits flush and covers 3/5th of the top board, that is the reason nothing can be soldered there. It covers 2 of the the screw holes as well, so there has to be a bit of retention force on the board to board connection, i am trying to include two additional threadet pillars between the boards in case the board connectors provide not enough though.