Noise Ground with a DDS ?!!

Hi,

I'm using a Direct Digital Synthesizer (AD9833) .

I would like to know how can I isolate the digital ground and the analogic ground.

I have to much noise on the analogic output and it seems to be the noise ground .

What others solutions can i use to minimise the noise ground ?

Best Regards.

The layout is critical. There is informative layout and grounding design guidelines on page 14 in the data sheet below.

You should connect digital ground with analog ground by ferrite bead.