madbeanpedals::forum

Projects => General Questions => Topic started by: mah62 on June 06, 2016, 09:42:39 AM

Title: Stutr purple blob
Post by: mah62 on June 06, 2016, 09:42:39 AM
Hi,
just looking at the layout for the Stutr. Does anybody know what the purple blob in the middle of the layout is? (Stupid question, I know - obviously Brian knows)!
Mark
Title: Re: Stutr purple blob
Post by: daleykd on June 06, 2016, 11:47:06 AM
I think it's a top and bottom ground plane connection between the two isolated ground planes.
Title: Re: Stutr purple blob
Post by: mah62 on June 07, 2016, 02:36:13 AM
Thanks for the reply. I thought vias were used to stitch ground planes.
It dosen't seem to make sense. If the purple blob is copper on the bottom layer
(I  assume), then surley the 2 zones are no longer isolated - so my question is: what
is the point?
Secondly, how to you actually render this in Eagle? Do you use the line tool and if so
how do you avoid isolation gaps when you click on Ratsnest?
Mark
Title: Re: Stutr purple blob
Post by: m-Kresol on June 07, 2016, 07:39:17 AM
i think daleykd is right. I assume this is done to somewhat separate the LFO portion from the audio part to minimize potential ticking. Nevertheless, both parts need to have a GND connection.

In eagle, I'd use the line tool to draw the connection. It would then isolate the line from the rest, therefore use the "name" tool to name it GND which should connect the nets. Haven't tried this though
Title: Re: Stutr purple blob
Post by: mah62 on June 07, 2016, 11:51:46 AM
Thanks Felix for the reply,

I have just tried it in Eagle and it works - How dumb of me not to realise that
any copper drawn with the line tool is "nameable"!

I still can't get my head around it being "somewhat separate".
The two planes are still both connected to GND aren't they?

Thanks again ,guys, for the (positive) feedback :-P

Mark

Mmm, my brain hurts!
So this somehow isolates the LFO from the audio circuits