PCB design is full of questions: How much current can this trace handle? What length and width does my trace need to have in order to achieve a given impedance? How much separation do I need to maintain between traces to avoid high voltage arcing? The list is endless.
Answers to all of these questions can usually be found by using a simulation tool or working through formulas. The Saturn PCB Toolkit is a free tool that fills the void between hand calculations and a full blown field solver. It can be used to calculate many parameters for PCB design.
Calculators for conductor impedance and conductor properties are extra useful, and make calculating voltage drops over long traces a breeze. The Bandwidth and Max Conductor Length tab helps to quickly determine the critical length of the design; that is the point where you need to start treating traces as transmission lines. That threshold informs you of how much work is ahead, also guiding your component placement in order to keep traces short so that you don’t exceed that borderline.
Avoid costly redesigns. Knowing these numbers will help you discover if you’ve accidentally (or unknowingly) violated the laws of physics and your board does not work. This is especially true for projects that employ high speed or high power signals where a few mm of extra trace length can make the difference between a working project and a pretty paperweight.
