I have a design where I want to make some arbitrary pad shapes, such as triangles. I can draw them in the layout just fine with the polygon tool, but I can’t figure out how to connect them to the pads on my ICs. Since everything in Eagle is counterintuitive, what is the process to accomplish this?
Thanks for any help.
I found a solution, but it seems somewhat kludgy.
First, make a new part that is nothing but a small surface mount solder pad. That allows electrical connections to be made to arbitrary floating points on the layout.
Then, draw a polygon wherever necessary and put the floating pad part inside or connected to it.
Lastly, create a special name just for that NET and polygon, so that they connect electrically and stay isolated from everything else.
Each trace in eagle has a name. Usually, it’s just an automatic name. If you select the name tool and click on a trace, you can change it’s name. you can do this in the schematic as well (though you name nets in the schematic). So, create you polygon and then give it a name (poly1, for example). Then, any traces you want to connect to poly1, just name them poly1 as well and you are in business.
By the way, this is how you make a ground plane - draw a rectangle and name it GND. All traces named GND now can be connected to it.
Philba:
Each trace in eagle has a name. Usually, it’s just an automatic name. If you select the name tool and click on a trace, you can change it’s name. you can do this in the schematic as well (though you name nets in the schematic). So, create you polygon and then give it a name (poly1, for example). Then, any traces you want to connect to poly1, just name them poly1 as well and you are in business.By the way, this is how you make a ground plane - draw a rectangle and name it GND. All traces named GND now can be connected to it.
A ground plane isn’t the kind of situation I meant to ask about.
I wanted to route individual polygons to individual pins. With your method how do you route a pin to a polygon across the board? Yes, you can rename a trace, but the problem is before a trace is even laid. Eagle won’t let me make an electrical connection to something that isn’t a pad. Since I can’t define an electrical connection I can’t route a trace. The solution I posted before gets around it by creating a pad that can be used for normal routing.
Does that make sense?
You are making it too hard on yourself. First off, don’t use the autorouter for this. So, name your net “POLY1”. In board view, create your polygon where you want it and name it POLY1. Then use the route tool and start from a pin that’s on the POLY1 net and route it to your polygon. It won’t behave like a pin - just route into the polygon. Once it’s inside the polygon, it’s connected. Hit ratsnest to be sure.
Philba:
You are making it too hard on yourself. First off, don’t use the autorouter for this. So, name your net “POLY1”. In board view, create your polygon where you want it and name it POLY1. Then use the route tool and start from a pin that’s on the POLY1 net and route it to your polygon. It won’t behave like a pin - just route into the polygon. Once it’s inside the polygon, it’s connected. Hit ratsnest to be sure.
I’ve never used the auto-router in Eagle. Too many bad experiences with other auto-routers…
I think your solution involves more than you have said. Here are the steps I took after reading your last post:
Create new board
Insert DIP package
Draw polygon
Now where is this net to rename? I can rename the polygon but I can’t find any net. Eagle won’t let me create an electrical connection from a pin to a polygon, and it will not let me start routing on any pins that do not have an electrical connection.
Go to the schematic view. The connections between pins are made with the net tool. Perhaps you used the wire tool instead? If you did, delete the wires and draw your nets. Then use the name tool to rename the net to POLY1 (or what ever you are using as the name). Verify the name using the info tool.
Then flip to the board view and go from there.
Philba:
Go to the schematic view. The connections between pins are made with the net tool. Perhaps you used the wire tool instead? If you did, delete the wires and draw your nets. Then use the name tool to rename the net to POLY1 (or what ever you are using as the name). Verify the name using the info tool.Then flip to the board view and go from there.
Oh, you’re involving the schematic tool!
I was just operating from the board layout. If I flip from that to schematic view there is nothing in the schematic view.
When I tried starting with a schematic before, I had to create a new “power supply” for every polygon in order to get separate nets in the board layout.
Not creating a schematic is really wasting the power of eagle. I’m not even sure it will work correctly with out a schematic.
edit: OK, I just created the following board. In schematic view, I added 2 single pins (pinhead lib, 1x1). Drew a net between them. Named the net poly1. Switched to board view. Drew the triangle polygon. Named it poly1. Routed a trace from each pin into poly1. Hit ratsnest and got the following. Took me about 3 minutes (and about 10 fiddling with getting the image exported and uploaded). This isn’t that hard if you do it right.
Philba:
Not creating a schematic is really wasting the power of eagle. I’m not even sure it will work correctly with out a schematic.edit: OK, I just created the following board. In schematic view, I added 2 single pins (pinhead lib, 1x1). Drew a net between them. Named the net poly1. Switched to board view. Drew the triangle polygon. Named it poly1. Routed a trace from each pin into poly1. Hit ratsnest and got the following. Took me about 3 minutes (and about 10 fiddling with getting the image exported and uploaded). This isn’t that hard if you do it right.
Thank you for taking the time to put that together.
