Eagle PCB Ground Plane Question

[Algar_emi]

Hi. I got a good question for other Eagle PCB users. It is something that bug's me for sometime and I was not able to find a real solution.

When I create a ground plane, I use "Polygon" and specify a "spacing" so the ground is insulated from the part's pins.

What I want to do is to be able to connect some pins to the GND plane. I'm doing it manually for now just before the printout of the layer image, but it is cumbersome and time consuming.

The PCB I'm working on right now is having maybe 100 gnd connections to the gnd plane. I don't want to do that manually

Any help would be appreciated.

Thanks...

 

[Thomas]

I think the easiest way is to (re)name the polygon GND. Then click the ratsnest button and the image will be redrawn with the new connections.

 

[Algar_emi]

Thanks for answering. A few questions to clarify the topic:

-How do I assign a specific part pin (like a pin of a transistor, smd package for example) to the GND layer?

-How Do I rename the polygon GND?

Thanks in advance...

 

[pinkmouse]

To assign grounds, use the supply library, it has several symbols in there for different ones so you can separate analogue and digital for instance.

To assign the polygon as a ground plane, click on the polygon button, then type the name, such as AGND, (use the same name as you used on the schema), into the text box, then draw your plane. Then click on the net button to draw the plane on screen.

 

[Algar_emi]

Here a small description on how to create a gnd plane and connect parts pins and pad to this ground plane:

-Using Polygon command select isolate value, then draw the ground plane surface.
-Using View/Info command, note signal variable name for this ground plane, ex: S$30 or using the name command rename it to GND, AGND or DGND
-Using Signal command, connect all the part's pins that connect to the ground plane.
This will assign a common signal name to all this pins.
-Using the Name command, change the name of the previous signal line to the ground plane name
-Press the Ratsness command, all the part's pins are now connected to the ground plane.
-To assign pad to gnd plane, draw a short wire using the Wire command on the same layer as the ground plane. Then using the Name command assign this wire to the GND layer.

 

[sagarverma]

You can make ground plane using the following steps

1. Name the all similar traces (eg ground) with the same name (eg GND).
2. Select ripup option and give GND in the command line (of eagle). Press enter.
3. Select Polygon fill and give GND in the command line and press enter.
4. Draw a polygon whereever you need the Ground plate.
5. Click on Ratsnest.
6. Ground Plate will appear.

You can use the same technique for any signal (Vcc, Vee etc).

 

[sklimek]

Here is a step by step which is bascially the same as the above two post but is helpful if you forgot a step or just need a tutorial.

http://www.interq.or.jp/japan/se-inoue/e_eagle32.htm#1

Stan