How to make thermal vias in a part

Question

Hello I am working with some high end LED parts and I need to make thermal vias and a nice heatsink area. I would like to know how to make the copper area and or the vias when designing a part be assignable to a net. That way I can join the thermal relief area to a powerplane if necessary. Currently I am having to manually heatsink each led every time which is dramatically time consuming.
Thanks!

Answer 1

Acidshock,
I would recommend that you create a custom footprint. For the heatsink area, just add a SMT pad (Place >> Pin... select SMD) and configure it to have the shape that you are looking for.
If you want to have it automatically connect to a specific net, then you need to modify or create a custom symbol/component in Multisim and add the extra pin that references the SMT pad you just created in the custom footprint. In this way you will transfer your design from Multisim to Ultiboard with the heatsink pre-configured to a net.
If not, then you will have the SMT pad every time you use your custom footprint, however, you will need to manually use the Netlist Editor to assign that pad to a specific net.
If what you need is a via for this purpose, then instead of SMT pad, use a normal through-hole pin, just configure the pad shape accordingly to fit your heatsink needs... when you place the Pin (remember you are creating a custom component), once placed double-click on it and find the tabs for manipulating the shape of the pad.
I hope that helps,
To get more information on creating custom components in Ultiboard and Multisim check the following tutorials:
http://zone.ni.com/devzone/cda/tut/p/id/5631
http://zone.ni.com/devzone/cda/tut/p/id/3173
Nestor
National Instruments