How do I control pad to polygon connection?

Don Gibson schrieb:

Perhaps I'm missing something, but now (using Eagle 7.6.0) any pads

matching the polygon signal are connected by hair-thin traces, not by

the solid pour I would expect.

 

For example on R4 I would expect to see no

isolation between the through-hole part (lower pin) and the Layer 16

(GND) polygon. The designs pass ERC/DRC - is there a parameter in the

autorouter setup I can adjust to cure this?

 

What controls this behaviour?

I assume you included an image, but that didn't make it from the crappy

E14 web-interface to the newsgroup. So I have no idea about "R4" or your

particular problem.

However, thermals are not related to the autorouter, but a property of

the polygon. See the HELP and the manual for POLYGON, what you can do

with them, and how the parameters are set.

Tilmann

On 29/09/16 00:46, Don Gibson wrote:

Perhaps I'm missing something, but now (using Eagle 7.6.0) any pads matching the polygon signal are connected by hair-thin traces, not by the solid pour I would expect.

 

I don't think this is something that has changed.

For example on R4 I would expect to see no isolation between the through-hole part (lower pin) and the Layer 16 (GND) polygon. 

The designs pass ERC/DRC - is there a parameter in the autorouter setup I can adjust to cure this?

The "isolation" is for thermal reasons - it makes it easier (possible,

in some cases) to solder the pin to the pad. You can turn thermals off

for the polygon but you shouldn't. The thickness of the traces

connecting the pad across the thermal barrier is set by the "width" of

the polygon.

Ok so the resolution was the boundary thickness (line width) of the polygon, combined with the ISOLATE parameter. 

It seems strange that there is no granular control of this style - the size of the pad and the polygon boundary should be related otherwise large pads and small pads on the same polygon behave very differently.

Thanks for the help !

Don Gibson schrieb:

Ok so the resolution was the boundary thickness (line width) of the

polygon, combined with the ISOLATE parameter.

...and the THERMALS property, probably.

It seems strange that there is no granular control of this style -

the size of the pad and the polygon boundary should be related

otherwise large pads and small pads on the same polygon behave very

differently.

If you need different behaviour at different parts of a polygon area,

simply draw it as more than one (overlapping) polygons with different

settings. For example, I often combine polygons with and without

thermals to get the desired copper pour (thermals where necessary for

soldering, but not where the polygon serves as a heat sink).

Tilmann