Tag Archives: solder mask

Happy St. Patrick’s Day!

And some trivia. You may have noticed that the soldermask used on most PC boards is green, as is the paint used on most steel truss bridges. Why is that? And what do the two things have in common? Why green PCBs and … Continue reading

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A Sticky Situation

The surface tension of liquidus solder exerts a considerable pulling force on a component during reflow. This is why, once upon a time, small components could be relied on to self-align on SMT pads during reflow. They still can, of … Continue reading

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OMG and MacDermid? OMG!

Not nearly enough attention is being paid to the pending acquisition of OMG’s electronic chemicals business by MacDermid’s parent company. This deal will throw even more market share to MacDermid, and the big question becomes how will smaller fabs (i.e., the vast majority of the North … Continue reading

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Super Small Via-in-Pad

Via-in-pad is an old issue that still pops up now and then. Our standard answer hasn’t changed: No open vias in pads. But one of the questions we get related to the subject is: “What if we make the vias … Continue reading

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US Commitments

When I heard early this month that Foxconn (Hon Hai) chief Terry Gou offered to train Americans in electronic manufacturing I recalled one of Apple’s excuses for putting its production in Asia, much of which went to Foxconn which now … Continue reading

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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 … Continue reading

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Passively Annoying

Passive components can be kind of offensive sometimes. I can understand them in analog circuits or charge pumps. But the fact that we need to put them all over our digital logic is just rude. Technically, I understand why they … Continue reading

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Small Open Vias

Pad 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 … Continue reading

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Random Via-In-Pad Myth #5

Myth #5: When you need thermal vias, more is better, bigger is better Hmmm. Logically, this would seem to be the case. There are limits though; especially if you want a reliably assembled product. Older parts with heat slugs easily … Continue reading

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0.4mm Pitch BGA Redux

I’ve written about it before, and again here. When dealing with new technology parts, it’s really important to look up all of the manufacturer’s component information that is available. I’m going to quote from the Texas Instruments document “PCB Design … Continue reading

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