pin with multiple figs

[sg]

If we have a pin with multiple figs in a OpenAccess design (virtuoso
61X), how does router (CCAR or Catena) behave? Should it connect to
all figs by default or it denpends on some property on pin to decide?

 

[Andrew Beckett]

sg wrote, on 07/15/10 23:51:

If we have a pin with multiple figs in a OpenAccess design (virtuoso
61X), how does router (CCAR or Catena) behave? Should it connect to
all figs by default or it denpends on some property on pin to decide?

A pin with multiple figures means that all the figures are "strongly connected".
So the routers should (I've not checked this) only need to route to one of the
pin figures, since strongly connected means they are connected inside.
Potentially it could take advantage of the strong connect to act as a
feedthrough though.

Weakly connected pins are represented by multiple pins on the same terminal.

Must connect pins are presented by separate terminals (with pins on each), with
an attribute to say that the terminals must be joined. This is sensible, because
if they are must connect, then this implies that they are separate nets inside
the cell.

Regards,

Andrew.