Signal and ground traces on PCB layer

rtk

I'm looking for help on understanding signal and ground traces on the same layer on PCB's?

cblair

Hello,

There can be many reasons why you have a signal and ground trace on the same layer of a board or chip. These layout are usually described as co-planar type of geometries. The need for co-planar configurations may be the need for direct access to ground, to avoid any parasitic. The ground layer on the board may be electrically long to attach a via ground. There is a power layer between the signal and ground.

Hope this helped!

rtk

Is there a minimum distance that I need between ground and signal trace?

VivekK

Yes this depends on the type of signal trace whether it is single ended or operating in differential or common mode of operation. As well as the frequency of operation. If the traces are electrically close to other conductors the layout may also generate parasitics and will need to be considered. A simulation tool can help to visualize the current paths and help determine an appropriate spacing.