I'm making a symbol for the QFN20 and SSOP24 variants of the SIlicon Laboratories Si473x famiy devices. Apart from the SSOP having more NC and earth pins (which I can connect as duplicates), there's an extra pin (DYBP) on the SSOP which isn't brought out on the QFN. If I add this pin to the device, I get errors using the QFN package because it isn't connected.
Is it possible to have a pin in a device which is not available in all package variants? How?