2-layers PCB considerations for two different grounds

Thread Starter

Xavier Pacheco Paulino

Joined Oct 21, 2015
727
What should I take into account when designing a PCB with two different grounds? Let's say power ground and signal ground. I've heard of the use of ground planes. But if I have two grounds, would I have to create two ground planes? Or what would be a good way to distribute the grounds over the two layers? I've designed small PCBs for simple applications and this is not a problem. Now it's my first time designing a more complex one.
 

dendad

Joined Feb 20, 2016
3,071
Here is the ground plane from one of my BLDC boards. I know this is a 4 layer board but the same thing can apply on a 2 layer board.
There are 3 areas, and all are connected together at one point.
gndplane.jpg
Usually at the main power supply capacitor 0V.
The idea is to keep the different currents apart.
 
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