We have power traces in inner layer (the yellow traces). We have linked all our nets with traces taking care of track width based on current flowing into the nets.
Now, we are wondering if we should keep this like this or if we should create a polygon for each track (which I suppose might be benefical to spreading flow over a larger surface).
What would you do ? Would you create polygon and if yes how would you draw them to make them adjacent to each other and to delimit their borders ?
Best Answer
I would go with polygons for 2 reasons:
1) More copper = more area = less thermal problems due to current heating up the copper.
2) By filling the entire layer with copper, regardless PWR or GND, you are reducing the gaps that the prepreg can flow into when the fabricator presses the layers together. This helps keep things mechanically stable and ensures an even thickness of prepreg across your board.
Here is a useful calculator for calculating required trade width given copper thickness, current, and temp rise: http://circuitcalculator.com/wordpress/2006/01/31/pcb-trace-width-calculator/