Author Topic: Adding to or enhancing heat sinking polygons to existing SMD heat sinks  (Read 282 times)

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Offline colin99

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My circuit has some transistors with "adequate" polygons for heat dissipation - I'd like to ADD to these existing polygons - I have tried and I get errors -
I'd even consider adding closely adjacent "Non grounded and non-ground-plane polygons" to this layout and adding a solder bridge.
What I am finding is that when I add a polygon TOP and BOTTOM and add the tStop and bStop, it appears to incorporate the
polygon into the larger (all board encompassing) GND polygon top and bottom. Does this make sense?

Shouldn't one be able to make polygons within polygons and create their own NETCLASS or are polygons treated differently?

Bottom line - I am adding extra copper to the COLLECTOR of this transistor (that cannot be grounded...)

Any help will be rewarded accordingly! :-)
 

Offline Kean

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Re: Adding to or enhancing heat sinking polygons to existing SMD heat sinks
« Reply #1 on: November 27, 2020, 11:19:22 am »
Sounds like you need to adjust the Rank setting on the polygons.  Change Rank on the ground polygon to 2.
 

Offline colin99

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Re: Adding to or enhancing heat sinking polygons to existing SMD heat sinks
« Reply #2 on: November 27, 2020, 06:56:44 pm »
Bingo! that was it -

Thank you kindly!
 


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