On Aug 6, 2010, at 9:22 AM, Seroxatmad wrote: > If I am creating a component which states a hole diameter of 0.5mm should I > create it at that size? Also would a 1.5mm outer pad diameter be correct? Is > there any sort of rules I should follow?
You are the designer of your board so its all up to you. 0.5mm is 0.0196" which is rather small but not impossibly small. If you think its right, then use it. Make sure its the recommended footprint hole and not the size of the device's leads. Usually need a hole about 10 mils bigger for an easy fit. Make sure you measure on the diagonal of rectangular leads. Just how much bigger you need is a question to ask of your assembly shop. I typically use 0.030" holes in 0.050" pads for DIP TH parts and vias. Might drop the vias to a 35 mil pad and as small as 15 mil hole depending on the selected fabrication shop. As for rules, its a mix of what you as an experienced designer wants combined with what your selected PCB fab shop can do and recommends. If your design can stand it I recommend 10 mil traces with 10 mil clearances. Any sloppy PCB shop should be able to build that. If things are tight then 8/8, or 6/6. But don't use the smaller details just because you can. -- David Kelly N4HHE, dke...@hiwaay.net ======================================================================== Whom computers would destroy, they must first drive mad.
