We are doing a PCB which has both surface mount components and through hole components on it.
The surface mount components are on both sides of the PCB.
What’s the closest that a surface mount pad can be to a through hole pad?
We are doing a PCB which has both surface mount components and through hole components on it.
The surface mount components are on both sides of the PCB.
What’s the closest that a surface mount pad can be to a through hole pad?
Check your manufacturer's requirements. They will give you a minimum trace width/copper clearance. If you're having the supplier assemble the boards for you, generally the through-hole parts are done as a secondary process and the only restriction on spacing is the etch clearance.
Seeed Studios has a very good PCB Design Guide. It's worth a browse. But DerStrom is right, your fabricator and assembler will have the final say.
Position parts on the bottom of the board to allow room to hand-solder through-hole components - there will have to be clearance for a soldering iron tip without messing up SMT components.
It depends highly on the processes involved. Are the SMD components only reflowed? Do you have a wave process? What direction is the wave process, and is there sufficient space to not cast shadows? What parts are reto-fitted/hand placed? etc etc.