Electronic – Is it bad to route a trace edge of a rectangular pad

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I got a quick friendly critic from someone in production for the below trace that I should not route the trace from the edge of a pad. What he said that it would create an extra force to the trace that might cause problem especially for smaller pad size in the production.

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I could not really clearly understand what is the problem. If there is a force in the trace direction, I can imagine that it may break the trace, but is it something may occur during the pick and place machine or is it an after production concern? Could anyone please help me to understand what kind of problem may occur and how likely is it to happen?

Best Answer

Keep in mind that the solder mask will be expanded by some mils (the exact number depending on the manufacturing process you're designing for) around the pad so you'll get an asymmetric pad shape that will tend to pull the package. Probably not a big deal, but it also looks ugly. If you had a bunch heading off in the same direction (or, worse, antisymmetric on top and bottom rows) it might become an issue- symptom would be a rotation of the package during the soldering process.

The same trace seems to bend unnecessarily close to the left pad and is at an angle close to horizontal but not quite- try to maximize clearances and keep almost-horizontal traces horizontal. A 45 degree snap on angles works well for most purposes.