Decrease Noise between ground track and power supply track when design PCB Board
PCB Board designer can find the way to decrease noise between ground track and power supply track,
1st of all, add the decoupling capacitor among the power supply wire and grounded wires, widen the power supply track and ground track’s width, and the ground track had better wider than power supply ones to leading to their relationship: Ground track >Power supply track>signal track, and the width of signal track normally 0.2 to 0.3 mm, and the minimum width of the track can reach 0.05 to 0.07mm, while the power supply track is 1.2 to 2.5mm.
As for the digital circuit PCB board design, their ground tracks can be used to form a loop system as a ground network for further usage, engineer should be noted this way won’t work for the analog circuit system;
Choose great size of copper area as ground track is a way to use all those redundant space on the printed circuit board as ground area and connect to other ground lines, or design the printed circuit board to a multilayer one, so the power supply and ground track can use each layer separately;
Shared ground solution for the digital circuit and analog circuit
Nowadays more and more PCB boards are no more the single functional circuitry but with cross functions mixed with digital or analog circuitries, as a result of that, designer must be especially careful when designing like these, and take the mutual interference issues into account especially for the noise interference generated from the ground lines;
The higher frequency of digital circuitry, the more sensitivities of the analog circuitries, as for the signal lines, high frequency signal line must be as far away it can be as possible from the sensitive circuitry components, as for the ground track, and there is only one summary for the PCB Board designing.
So it is necessary to deal with the digital/analog shared ground issue within the PCB system, and actually inside the PCB itself the digital ground and analog ground is separated without any connection, but just there is a joint point on the external terminal such as socket;