Duplicate plane cuts for two ground planes?

[bobsun]

Hello,

I would like to ask a question on GND plane.

In order to provide double side reference plane for stripline signals I am using more than one ground planes (see doublegnd.png). The question is: If I am using more than one (two here) GND planes, do I have to make them exactly the same? Most of the areas on the two GND planes will be connected to GND signal, but there are also planes cuts that are connected to either GND_DAC, GND_DENC or other grounds.

Therefore, if I am having ground plane 1 and ground plane 2, do I have to make the cuts on them the same? In more detail, if GND_DAC is cut on ground plane 1, do I have to cut it again in ground 2?

Are there any pros and cons for duplicate planes cuts or not?



Thanks,
Bob

 

[marce]

I would look around the internet for as many articles on ground planes as possible, the general concensus these days is not to split ground planes. There have been numerous discussions regarding this over the years, but generally the view dont split the ground plane. It can cause more problems than it solves. The other problem is if you split the ground you cannot run a route over a split without consequences. For the majority of designs (all ) one contigous ground plane, you'll have less problems.

**broken link removed**
http://www.ieee.org.uk/docs/emc1206a.pdf
http://www.ultracad.com/articles/slots.pdf

This usually gets a few arthritic electronics engineers, sucking their gums and going, when I was a lad we had analogue ground, digital ground and so on, well times move on and with todays rise times, faster clock speeds, smaller components and denser designs one (1) ground is best.

 

[bobsun]

Dear marce,

Many thanks for these helpful links. I think I really need to read some theory first.


Bob