Do I need ground fill and if so how do I do it?


#1

I’ve said this before but I’ll say it again, I’m a novice.

Now, I’ve routed my PCB and I’m happy with the layout, but it’s all just traces without copper fill. Do I need a ground fill? I’ve come to this as a complete beginner and I just don’t know if a ground fill is needed or not. Any advice?


Ground plane erstellen, aber wie?
#2

Since no one has answered I will try. I am no expert so someone may correct me.

It is rarely a bad idea to have a ground fill. It will carry away stray noise.

To create the ground fill you just need to right click on a connector or pad that is part of your V- (GND) net and select set as ground fill seed. If you have more than one circuit with separate V- (GND) nets then you will need to set at least one seed for each net. After that make sure both layers are set as clickable (or which ever layer you want the ground fill on if you only want it on one) then go to the Routing menu > Ground Fill > Ground Fill (Top and Bottom).

Once it is done creating the ground fill you will see some of the ground fill is yellow and some is red. This is supposed to show if the ground fill is connected to ground or not. Unfortunately it can show connected ones as unconnected so don’t be too concerned. To fix ones you know are not connected you may be able to drag via’s on to the board and connect those areas on one side to a connected plane on the other side.

You can also add via’s around parts that need additional cooling but again be careful they are only on ground planes on both sides and do not intersect any traces other than ground traces.

If you place these via’s before creating the ground fill Fritzing can leave a space around them.


#3

You can also change Ground Fill Keepout, if you need more gap.

The red splotches in pads are connection points if you want to run traces.


#4

I have routed everything and it’s kind of ready, this includes traces for ground as I figured I had to do this.

Now I’m trying to simplify and get a ground fill so there are fewer traces and vias… But when I mark a few ground-connected vias and pads as ‘ground fill seeds’ and go to create a copper fill on one layer, I just get lots of islands of fill but nothing is connected to ground. Where am I going wrong?

( Also, the edges are rough and pixelated as though they are bitmaps rather than vectors. )


#5

Any islands that are overlapping the ground traces will be connected but show as not connected.

You said Copper fill and I just want to confirm you actually clicked ground fill not copper fill as copper fill will never connect to anything.

You only need to select one single pad or via that is part of the ground fill net. Fritzing follows that path and makes all the connected pads part of the ground fill.

Also note that ground fill will only be connected by small little tabs to the pads and holes. This is to make it possible to solder because if it was just solid the large copper area would take heat away fro the pad too quickly making the solder joint weak.

If none of this helped maybe upload a picture of a board after running ground fill.


#6

I used the function under the following menu path :
Routing > Ground Fill > Copper Fill (top)

It’s just not doing it for me. Should I have not routed traces to the ground connections of my parts?


#7

You do want the ground traces as without them Fritzing will complain and also there is a chance of something not being connected.

The issue seams to be with clicking copper fill not ground fill. It should be Routing menu > Ground Fill > Ground Fill (top) not Copper Fill (top)


#8

Hmmmm.

I have been wondering if my version is up to date. because it still says beta…


#9

Yes the program is still in Beta. You will see in the second picture it says Copper Fill (top) and right below it it says Ground Fill (top).


#10

AHHH! I’m an idiot.
Sorry.


#11

No worries. I have clicked the wrong one more times than I would like to admit. I also have some boards that take 10-15 minutes to generate fill so when you click the wrong one it is an agonizing wait for it to complete, then remove the fill and redo it correctly.


#12

Can I just ask. Is it a problem that the ground fill ( and copper fill ) are so jagged and pixelated; like a bitmap rather than a vector graphic? Does this come out in the fabrication process?


#13

I believe that is just how it is rendered. I inspect my boards under a microscope and none of the jagged edges are visible.


#14

While I don’t know anything about ground fills, assuming you are seeing the pixelization in Fritzing, export the pcb to gerber file->export-for production->gerber and view the gerber files in a gerber viewer (I use gerbv from the geda project). That is what the production house will see, and if it is jagged in the geber view then so will be the board. Note gerbv has varying qualities (lower to speed up rendering) so you probably want to use one of the higher (and slower) ones such as high quality.

Peter


#15

Hi guys. I’m working on a double layer tht PCB and I have some concernes about my ground. I have place ground fill and it seems that all GND pins are connected with the plate but Fritzing still shows them as unrooted.

Should it be that way? I can add some pictures in the evening.


#16

Copper fill fills areas without connecting to anything, and ground fill connects grounds.

If you ground fill it shows the grounds connected with ratsnests - black dotted line -. You can also double check if the ends are seeded and actually connected.