Ground paths and less cluttered ground plane

[TokTok12]

Hi all,

In my attached Eagle files i.e. schematic and board, I've got some unclear aspects feedback from my boardhouse in relation to my my ground plane and ground path.

1st issue: Firstly with the ground plane I'm being advised by my boardhouse that my ground planes and tracks are too close to the edge of the board. My boardhouse recommends 50 thou or mils margin. In all my previous board development attempts I've laid out my ground plane using the board outliune as my guide when laying it as you will notice from the attached board file or its screenshot.

Question: Does laying the copper pour with a certain margin away from the edge of te board affect the functioning of a board in any way?

Solution to the first issue: I'll lay the copper pour with a 50 mil margin away from the edge of the board.

2nd issue: My board house has identified the ground return paths for my Zigbee Module and PIC are all forced to follow a route around the bottom right corner of the board rather than a more direct path.

Question: Looking at the attached board file or screenshot what is the negative impact of having the ground return paths of my PIC and Zigbee module around the bottom right corner of the boardconverging

2nd issue continued: In addition they have mentioned if I were to concentrate on just one ground plane and try to keep all horizontal tracks on one layer even though this uses more vias I would have a less cluttered ground plane.

Question: Does this mean having a ground plane only on say the top layer not both layers?

Question: What would be the effect of having only one ground plane?

Question: How does having one ground plane make the ground plane less cluttered/crowded?

2nd issue continued: They also mention based on concentrating on one ground plane it would be more effective in its job e.g. L1 to COUT+ and L1 to F15 changing layer would give a more direct return path (use large vias).

Question: Why would having only one ground plane bring out better efficiency in the ground plane doing its job?

Here are the file attachments:
Eagle files i.e. schematic and board: View attachment SCH AND BRD.rar

Schematic screenshot:

Board screenshot:

I really appreciate any replies to the post.

 

[Kick]

hii,

for the first issue you can use min. 20 min clearance from the edge of the board.

 

[TokTok12]

hii,

for the first issue you can use min. 20 min clearance from the edge of the board.

Hi,

Thanks for the reply.Yes for 1st issues I'll apply a 50mil clearance before laying the new ground plane.

Regards.

 

[Mattylad]

Redo that PSU completely.

Do some research into switched mode PSU's and the switching currents in them.

As it it will be unnecessarily electrically noisy.

Look at your circuit diagram, look at the gnd connections for the PSU, connect them in that order with thick tracks - do not wander off elsewhere first. Then think about connecting everything else.

Do the same for the placement of the components.

Move the crystal so that its right on the pins and both connections to it are direct, not the way it is.