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VCC signal on ground plane

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aliyesami

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please see the image , the line in light blue is the VCC signal that the software has routed on ground plane , is it ok ? can a VCC trace run between the ground plane ?

thanks
Capture.JPG
 

the line in light blue is the VCC signal that the software has routed on ground plane , is it ok ?
"A software" doesn't route anything on it's own without your allowance, respectively routing rules.

It doesn't look like an actual ground plane, more a ground fill. Impossible to detect if the two ground pins visible in the screenshot are still connected. If they are, obviously not on a direct way.

It's sometimes necessary to create mixed planes. But you have to take care that the plane function is maintained. I doubt that it's the case here. You have many unconnected ground isles that could/should be deleted.
 

Rip it up, learn how to route and start again, that is a pile of absolute rubbish (and I am being polite here), every bit I have looked at, all the signals follow stupid paths......
 

It seems that the rules haven't been properly configured because all the traces have identical width and clearance too. So fixing the rules should have priority over rerouting the board.
 

few questions :
1- if i click on info in eagle cad on the polygon and it says GND is it a ground plane or a ground fill?

2- which rules i have to properly configure ? as its impossible to route these lines manually since the circuit is complex and also the space is confined, so i am using autorouting features of eaglecad.
 

few questions :
1- if i click on info in eagle cad on the polygon and it says GND is it a ground plane or a ground fill?

2- which rules i have to properly configure ? as its impossible to route these lines manually since the circuit is complex and also the space is confined, so i am using autorouting features of eaglecad.
Manual routing always gives the best results. Complexity is a good reason to route manually, not to use the autorouter.
 

its impossible to route these lines manually since the circuit is complex and also the space is confined, so i am using autorouting features of eaglecad.

Codswallop!
That is not complex - as marc says - rip it pup and think about it again.
You have a big split in your ground with the thin blue line, lookup splits in groundplanes.
 

ok i will rip it up . do I lay the ground plane on the complete lower side or leave some space for any traces that might have to be routed on the lower side?
also do i need a power plane on the top layer or just route the VCC lines like any other lines? i do have RF chip on board that runs at 900mhz . so should i isolate its ground?

thanks

- - - Updated - - -

also here is a ground plane sample i found online made by some professoinal.
doesnt it also have sections of ground isolated n forming islands?
trying to compare it with my design , can you point out whats the difference?

thanks
 

First lay tracks that are controlled impedances without vias and good ground planes with microvias as needed.

Then partly lay tracks dominated in one direction and orthogonal ones.
Then repeat visa versa on other side for balance of signals.
Complete tracks with orthogonal connections and vias where required.

Although not perfect, and planning is required on layout to minimize vias, at least the track directions are more consistent on each signal layer.

Remember Vcc is not a signal but must be a low inductance wide area distributed power bus
Use microwave decoupling caps where needed with small series R.
 

if i click on info in eagle cad on the polygon and it says GND is it a ground plane or a ground fill?
The difference between a polygon and a plane is mere terminology, they both come down to the same: a solid copper area on the board.

Most PCB designers will interpret a "ground plane" as an inner layer that is connected to the ground potential and doesn't carry any other signal traces. A "ground polygon" is just a copper fill on a signal layer, with traces and possibly other polygons surrounding it.
 

RF and autorouting will not work together, autoroute the board and it will never work...
 

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