Screaming Circuits: Tips and tools

PROTOTYPE AND SMALL VOLUME
PCB ASSEMBLY MADE EASY

Via in Pad x 8

Here's an interesting via in pad case. On the one hand, the footprint is very symmetrical and clean looking. On the other hand, it has open vias in the pads. At first glance, I thought this was a DIP footprint... Read more

More Thermal Examples

Speaking of thermal relief... Here's an interesting example I ran across the other day. Thermal relief can be a pain. If you've got a high current device, you may want more than just the thin little connections, one per side,... Read more

Electrolytic Ambiguity

I've written about ambiguity a few times before, like this post about fiducials. But I'm not talking about the PC board today. I'm talking parts. More specifically, I'm talking about silk screen markings for your parts on the PCB. Diodes... Read more

Fiddling with Fiducials again

I recently posted a note about fiducials but I didn't have any images. Here's a couple of examples: This first example shows what IPC would like to see. If this is an individual board, this would be it. If it... Read more

Ambiguity

It's pretty important to have unambiguous polarity markings and pin one markings printed on your PCB. In theory, for SMT parts, it really shouldn't matter; the centroid would take care of the placement orientation. But, you may have noticed that... Read more

More CAD footprint woes

AT this point, I really shouldn't call them "woes." More like business as usual. I'm talking about the need to make custom footprints, or at leas modify footprints. Back in the old days, the only thing needed to make footprints... Read more

Thru-Hole Parts

Screaming Circuits uses machines to place surface mount parts; even if it's just one board. Thru-hole are a different story though. Way back in the cobweby section of the building, we do have a thru-hole part sequencing and insertion machine.... Read more

QFN Custom Stencil Layer in Eagle

It's been said over and over that you don't want to leave the solder paste opening wide open for a QFN center pad. 50 - 75% paste coverage will get you bets results. With full coverage, your QFN can end... Read more

BGA pads with Vias

No. This isn't a closeup of an owl face. There is still some debate on how best to create a land pattern for a 0.4mm pitch BGA. We recommend soldermask defined pads at that pitch. But that's not really what... Read more

Small Open Vias

Parts change and so do vias. Our standard policy here is that open vias in pads are bad. We from time to time recommend ways to plug them. Generally, you have several options. Like this post shows. However, with vias... Read more