Eagle PCB Footprint Question

Community PCB Design
1

Is there a way to connect spaced pads together within a package in Eagle?

There doesn’t seem to be a wire tool. I’m afraid if I use SMD pads to bridge other pads together I will get an error farther down the road. I tried using the polygon tool and it screamed “Layer Abuse” 12 times in DRC.

In this specific case I am trying to make a symbol that accommodates half or full size oscillator modules. Pin 4 should connect to pin 7, and 8 to 11. Not needing to draw extra traces every time I do a layout would be nice.

Is it not possible? Any help is appreciated.

2

Why would you want to?

If you connect them to the same net, you can connect the pads together when you route the board. I’d leave the pads separate and take care of bridging the identical connections in the schematic. That way you don’t have some confusing connections on the layout that don’t appear on the schematic.

3

Shifted:
Why would you want to?

If you connect them to the same net, you can connect the pads together when you route the board. I’d leave the pads separate and take care of bridging the identical connections in the schematic. That way you don’t have some confusing connections on the layout that don’t appear on the schematic.

That describes what I do currently. I feel like it kludges up the schematic and makes things more confusing than they need to be. It would be nice to have only 4 pins in the schematic. I like to keep my schematics as minimal as possible without extra “what are those for?” pins that are a product of something strange in the layout world. Looking at the PCB layout there will never be any confusion because it’s obvious (to me) what is going on.

Also, I’m still trying to learn about complex routing work in Eagle. It seems limited in what it can do for individual component footprints, so I am hoping to learn something new.

4

skrasms:
Is there a way to connect spaced pads together within a package in Eagle?

No.

skrasms:
There doesn’t seem to be a wire tool. I’m afraid if I use SMD pads to bridge other pads together I will get an error farther down the road. I tried using the polygon tool and it screamed “Layer Abuse” 12 times in DRC.

If I've understood your request, you'd like to have the

library part (for an oscillator module in this case) come

with traces/tracks between pins that are aways connected.

Is that correct?

The library part can only have pads and outline, it can’t

have anything on the layers (for obvious reasons).

Also, you can’t expand the pads beyond the max size

allowed (i.e. can make a pad go from one pin to another).

skrasms:
Not needing to draw extra traces every time I do a layout would be nice.

Why not? If you placed, say, a

microcontroller IC would you also be too lazy to connect the

power and ground?

By showing all the electrical connections to a device you are

making an accurate and clear record for the person reading

it later (even if that is only you).

You could make a one time schematic diagram of the

component, save it, and import it by cut and paste. I do

that quite a bit for repetitive circuit fragments (like LDOs

with two capacitors, uC programming headers, etc.)

5

Many other packages (including Pulsonix) allow such “ungated pins”, which can be automatically connected to the appropriate nets on the PCB. They can make a schematic less cluttered. That said, I mostly use them for connectors and switches, otherwise I have to answer questions about apparently missing connections.

Leon