3 ms·

For simple and slow communication busses on hobbyist boards, sure it probably doesn't matter. But I really can't trust this very superficial attempt to prove a

For simple and slow communication busses on hobbyist boards, sure it probably doesn't matter. But I really can't trust this very superficial attempt to prove a negative with regards to a very complex phenomenon that I do not think he understands, especially since he mentions nothing about inductance, reflections, or impedance changes. Hell, RF experts with decades of experience will still find new corner-cases and issues with PCB layouts when it comes to analog signals. In terms of "actual wisdom" regarding 90 degree traces: Some time ago at my job we had to actually scrap a PCB because of right-angle traces causing too much interference. The end effect was a comb filter on the signal and a ton of emitted RF interference. TLDR: Yes, the phenomenon is real. Do not trust these hand-wavy attempts to dismiss it.

everybodyknows 7y ago
First sign of the author's confusion: >a square of copper two millimeters on a side has the same resistance as a square of copper ten millimeters on a side. It’s counter-intuitive. The phenomenon is perfectly intuitive for anyone who understands DC resistance of metals, and the geometric assumptions of the "sheet resistance" thought experiment. Resistance is proportional to conducter length divided by cross-sectional area. For a sheet conductor, cross-sectional area is thickness times width. A necessary assumption, unstated in the article, is that the hypothetical test circuit somehow makes perfect, uniform electrical contact over the entirety of both of the sheet's chosen "width" edges.