Daisy Seed and ground planes

Hardware Development
1

Hi guys

I’m building some PCB hardware and everything works great, but my first prototype is a little noisy (background noise when i turn up the volume).
I know that a ground plane would help, but i’m confused because i also know that the daisy seed has digital ground and analog ground.

Which net should the ground plane be?
Should i have 2 ground planes, one for each net on different layers?

When looking at the daisy pod, it seems that there is only a small plane near the audio in and out traces, should i just make a small AGND plane around those?

Any info you can give would be very helpful, thanks!

2

I am also working on a design with the daisy seed and wondering the same thing. The spec sheet says to connect agnd and dgnd together on your own hardware, but as someone new to mixed signal design, I wonder where you would do this. Can you have a single ground plane that connects to both dgnd and agnd pins, as well as the audio jacks? Or will you experience digital noise in your audio that would be mitigated by separating the grounds in some way?

3

according to the daisy manual, you always have to connect AGND and DGND together
(no clue why thats not just done internally…)

Can you have a single ground plane that connects to both dgnd and agnd pins, as well as the audio jacks?

yes, have done that in our own project and no noise at all (didnt expect the daisy to have such good audio)

1 Like
4

When i test the seed with a multimeter, it seems that both grounds are connected internally :man_shrugging:

Thanks for the answer regarding the ground plane, i’ll try the same!

5

I measure about 17.5 ohms between AGND and DGND on a Rev 7 Daisy Seed.
Only ‘connected’ in the loosest sense of the word.