[gta02-core] ECN0024 (GPS ground and layout)

Werner Almesberger werner at openmoko.org
Wed Oct 7 15:19:32 CEST 2009


?lvaro Lopes wrote:
> One idea is to have a separate ground for the RF part, and connect
> it to digital ground at one point, forming some sort of ground peninsula,

Whether to split ground planes or not seems to vary mainly with the
designer, less with the design. 

To take random examples from a quick google search, the pro-split side
has a quite convincing example here:
http://www.signalintegrity.com/Pubs/news/9_04.htm

And so does the contra-split side (also check out the link to the 2001
article):
http://www.hottconsultants.com/techtips/split-gnd-plane.html

My interpretation is that splitting ground planes gives you more
control, but at the cost of increasing complexity and the risk of
unintended consequences.

> We should also have these
> ground planes (RF) filled with through-hole vias, to avoid EMI emission
> (and maybe mitigate interferences).

Putting that RF into a "cage" sounds good to me. This should also help
to reduce ground impedance.

- Werner



More information about the gta02-core mailing list