| T O P I C R E V I E W |
| Marzipan |
Posted - 17 Apr 2009 : 15:58:22
I have a few surface mount IC packages with heat sinks. I want a heat sinking pad on the footprint. But I don't want to have the Heat sink as a pin in the schematic.
At the moment the only way I'm making the components is to make the heatsink a pin and then match it to a schematic which has an extra pin which I then don't connect.
There must be a better way. What is it?
The help mentions a type of pad called a 'free' pad. But it doesn't say how you can make a free pad in your PCB schematic.
*\__/ |
| 2 L A T E S T R E P L I E S (Newest First) |
| Marzipan |
Posted - 20 Apr 2009 : 14:35:55
Thanks
I didn't realise you could have more PCB Pads than Schematic pins.
That's really helped me out.
*\__/ |
| Peter Johnson |
Posted - 17 Apr 2009 : 17:54:29
Free pads don't exist in symbols. They are called free pads because they are only added to a design, and can therefore be freely edited as symbol pads cannot.
There is no requirement that a pad in a pcb symbol be connected to a schematic pin. It's perfectly reasonable to leave it unassigned - after all, that already done with mounting holes for connectors and the like. An unassigned pad like this can be connected to a net in the pcb. It will generate a warning (for information) but not an error.
Look at the technical menu on the main website. There's an item about custom pad shapes on the FAQ page which should be of help. |
