HDI component clerance

[dlo]

What have you found to be the minimum component clearance for reliable high density designs? Right now I've managed to get boards made with 0.005" spacing. For example the distance between two 0201 capacitors is 5 mil apart. I've also been making them with 0.01" spacing from the edge of the board and it seems to be ok with the manufacturer. What has been your experience with component clearances and clearance from board edge?

[mairomaster]

Anything below 8mil (0.2 mm) even for the small 0201 components is being too close in my opinion. IPC agrees with that as well.

[dlo]

Thanks mairomaster !! I should have checked the IPC specs. In your experience, have you used 8mil or went with something higher?

[Paul van Avesaath]

Anything below 8mil (0.2 mm) even for the small 0201 components is being too close in my opinion. IPC agrees with that as well.

i find it kind of funny becauase if you have a 4mil clearance between traces. why do you need a 8 mil clearance to the components.. I can undestand why the IPC says it should be bigger.. but for manufacturing it would not be any different..

[robertferanec]

i find it kind of funny becauase if you have a 4mil clearance between traces. why do you need a 8 mil clearance to the components..

I believe it will be something with how precisely the machines can place the components. Etching PCB is probably easier then trying to pick up a component, align it and place it very precisely between two other components (and do this very quickly).

[Paul van Avesaath]

closest i have gotten 0402 is 9.85 mil. guess i am safe!

i meant distance between track and component... in this case.. but i guess i read the question wrong.. its too early to be thinking straight.. haven't had my 5th cup of coffee yet..

[robertferanec]

haven't had my 5th cup of coffee yet..

[mairomaster]

Thanks mairomaster !! I should have checked the IPC specs. In your experience, have you used 8mil or went with something higher?

I've used down to 10mil, but I've seen 8 used on some dev boards successfully. Just to make it clear, I meant IPC recommends bigger spacing, not 0.2. Maybe it was 0.25, don't remember exactly. I wouldn't really recommend going too small for serious mass produced designs where a good yield is expected.

[dlo]

Thanks a lot for all your inputs! Very interesting insights and always happy to learn more.