 |
 |
 |
 |
|
|
 |
 |
|
|
 |
 |
|
|
 |
|
 09 Mar 2010, 7:21 PM
|
emin
Joined on 01-06-2010
Posts 9
|
comps won't connect to ground plane
|
|
|
Hey guys, Is net connectivity to a plane that important?
my components are on the top layer, almost all SM. I got a ground copper pour on that layer. I took a screenshot to show. The two circled free vias pinch my pour (top layer) and ground plane( inner 3) together. net DGND is assigned to inner 3.
as you can see, the pads that give errors are already connected to the pour. How come ORCAD doesn't see them connected to the ground plane? I didn't use the default GND pour as my ground (it's disabled currently) do you think that is the reason?
Thanks
|
|
|
|
|
|
|
|
|
10 Mar 2010, 1:42 AM
|
Flo
Joined on 28 Jan 2008
Germany, Lower Saxony
Posts 211
|
Re: comps won't connect to ground plane
|
|
|
emin,
If you do not want two planes to be connected to the GND, than why did you add two?
The one connected VIA is maybe the connection from one to the other pour, cause looks like all other connected pins are SMD?!
Layout will need than one pin to be connected to both planes.
I mostly have one GND plane on a inner layer and a lots of VIAs for the SMD pads.
Regards
Flo
Join the google orcad-user-group.
http://groups.google.com/group/orcad-user-group
|
|
| |
|
|
|
|
|
|
|
10 Mar 2010, 10:17 AM
|
Ron_O
Joined on 09-03-2002
Thorndale, Canada
Posts 1,629
|
Re: comps won't connect to ground plane
|
|
|
If you want the planes connected together they need to be the same netname. Is the top pour assigned the same netname ie. DGND, as the inner3 layer?
Ron O
See the Orcad User Forum on Google Groups:
http://groups.google.com/group/orcad-user-group?hl=en
|
|
|
|
|
|
|
|
|
|
11 Mar 2010, 3:58 AM
|
emin
Joined on 01-06-2010
Posts 9
|
Re: comps won't connect to ground plane
|
|
|
All in all I got the TOP with a DGND pour, INNER2(routing) with a DGND pour and INNER3 as a DGND plane. the inner 2 layer might be redundant, but I wanted the SMD's to be able to connect to ground right off the pad, and I included a ground plane in case some SMD's didn't have the pour near them.
Yes they are both named DGND
for example, those pads to the left in my picture are all DGND, and are connected to the DGND pour as you can see, but they still give me the error of "not connected to a plane"
maybe it's just a good DRC?
|
|
| |
|
|
|
|
|
|
|
|
11 Mar 2010, 4:56 AM
|
Flo
Joined on 28 Jan 2008
Germany, Lower Saxony
Posts 211
|
Re: comps won't connect to ground plane
|
|
|
You told layout to connect all DGND pads to the DGND plane (IN3),
now you are using a DGND pour to connect the SMD pads,
so layout tells you, that you have not connected all pads to the plane (IN3).
I would delete the pour and add VIAs (fanouts) for the SMD pads, to connect them with the plane.
OR
You delete the plane settings and add another pour on IN3.
Regards
Flo
Join the google orcad-user-group.
http://groups.google.com/group/orcad-user-group
|
|
|
|
|
|
|
|
|
|
11 Mar 2010, 11:54 AM
|
Ron_O
Joined on 09-03-2002
Thorndale, Canada
Posts 1,629
|
Re: comps won't connect to ground plane
|
|
|
By default, Inner3 is a routing layer. It looks like you have changed it to a plane layer. You should avoid doing this as it creates padstack conflicts. Assigning it as a routing layer with a DGND connected pour should resolve the plane connection errors. Using one of the inner layers as a power-net pour will also provide better overall capacitive coupling and noise elimination.
Ron O
See the Orcad User Forum on Google Groups:
http://groups.google.com/group/orcad-user-group?hl=en
|
|
|
|
|
|
|
|
|
|
11 Mar 2010, 2:29 PM
|
emin
Joined on 01-06-2010
Posts 9
|
Re: comps won't connect to ground plane
|
|
|
Flo,
I tried the DRC without having my DGND plane enabled and the DGND net not assigned to a plane. I still get the error. Plus, I connect the SMD's to the top layer pour, and pinch the pour and the DGND together through those circled vias.
Kevinh and Ron_O,
Layer GND is disabled, layer inner3 is set to plane. I've also checked my padstacks, everything agrees with my layer usage.
I don't see why having my SMD's touch a pour which is already touching a plane doesn't constitute my SMD's touching the plane.
Thanks,
|
|
| |
|
|
|
|
|
|
|
|
OrCAD Community » OrCAD Community Forums » OrCAD Capture to OrCAD Layout » comps won't connect to ground plane
|
|
|
|