Tips for power circuits when doing PCB layout and design

1.Keep power and control grounds separate

Large voltage and current spikes from power circuits can generate disruptive interference in the control circuits, which are usually low voltage and current. For each power supply stage, you should keep power ground and control ground separate. If you tie them together in the PCB, do it in a point near the end of the supply path (most notably near the PCB ground connection).

2.Use an inner layer for the control ground

In case you are thinking about using a multilayer circuit board, use the top layer for power traces, the bottom layer for control traces and an inner layer for the control ground. The large ground plane in the middle layer will offer a small impedance path for any interference from the power circuits and protect the control paths from it.

3.Make power traces wider to withstand higher currents

This is actually a general tip, but it is more important for power circuits. You should size the width of the wire of each power path according to the current that flows through it. Failing to do so can generative excessive heat and burn the wires. You can use this online calculator to calculate their width.