Altium Designer官方资料：我们听过的关于PCB设计的最糟糕的建议

At Altium, we’ve been in the PCB design business for over 30 years. In that time, we’ve seen a lot of innovations—and a lot of mistakes. It seems every engineer has some advice to offer on printed circuit boards, and not all of it is good. Here’s a roundup of some of the worst PCB design advice we’ve heard.

At first glance, this seems like sound advice. When soldering a circuit into place, a via hole in your PCB can cause any number of problems, which can ultimately damage the circuit or even the entire board. Therefore, a lot of designers put a blanket ban on via in pad.

However, some situations in modern PCB design make via in pad necessary. It can help with things like heat management and allows for closer placement of bypass capacitors. So if you get into the mindset of just not using via in pad, you might be shooting yourself in the foot when a via is needed, as you won’t know how to do it properly.

Vias in PCB design aren’t inherently good nor bad, but a tool, like any other. If you know how to use them, they can be helpful in a multitude of ways. If not, you’ll only end up ruining your work. So you CAN avoid them, but it’s much more useful to learn how to use them correctly and have another tool in your design arsenal.

Avoiding 90 degree angles is a common design tip repeated in classrooms and by veteran PCB designers. It’s an admonishment that has, in the past, had some merit to it. Many older PCB design tools were unable to handle 90 degree angles well. Acid can collect in those 90 degree corners, causing etching problems and other issues. Therefore, 45 degree angles have always been preferred for routing.

However, while this still may be a problem for some PCB hobbyists, modern professionals use alkaline etching nowadays, eliminating acid traps. Recent studies have found that PCBs with right angles function perfectly well at speeds as fast as 2Gbps.

While the original reasons have gone away, there’s another potential problem with right angles. Because of the old stigma against 90 degree angles, many PCB design tools only support the more traditional 45 degree angles. If you have legacy software, or software based on legacy software and hasn’t integrated these advances into its design setup, then you may have problems including right angles in your PCB. But as long as your design tools are up-to-date, those 90 degree angles are nothing to be afraid of.

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