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[SOLVED] Layout hierarchy PIN connectivity issue

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The_Dutchman

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Hello all,

I have a connectivity issue in my layout hierarchy.
For demonstration I've recreated the problem of my layout in a few pictures.

The problem is with the connectivity of PIN's.
If I have 2 cells, each with a pin and I connect them together using intersecting metal, no connection is made.
The connection is only made if I draw a new connecting path/rectangle between the PIN's.
Why is the Layout tool not recognizing that it is connected ?

Pictures:

Schematic Cell 1:
**broken link removed**
Schematic Cell 2:
**broken link removed**
Layout Cell 1:
**broken link removed**
Layout Cell 2:
**broken link removed**
Top Schematic:
**broken link removed**
Top Layout (does not show connected although metal touches).
**broken link removed**
Top Layout (does not show connected although overlapping metal).
**broken link removed**
Top Layout (show connected because new path between pins).
**broken link removed**

Does somebody know?
Thanks!
 

Well, usually shorting two pins results in at least some
netlister confusion, if not outright refusal to participate.
Might begin with making the test case not entirely trivial
(and insane, i.e. one net, two names).

Then, look at your pin polygons and make sure they do
have purpose "pin" and that net names are properly
represented in the property list. Compare this to a
placed / drawn layout pin created via the menus.

Last, pins buried in lower levels of hierarchy do not
force connectivity at higher levels. Pins need to be
placed at top level to have effect.
 

You have to make sure to put the extract connectivity level high enough (>0) so connectivity is extracted to the lower hierarchical levels. This can be found under Options-> Layout XL-> Connectivity tab -> Hierarchy Controls -> Extract connectivity to level (fill number of hierarchy to check). Cadence forum also suggested to make sure the "Allow off-pin hierarchical connections" is checked.

After this make sure to extract layout connectivity to get the markers to be accurate. From then on the connectivity is checked automatically if the "Update connectivity when is design is modified ON" is checked (icon in the Options toolbar)

Then it works out fine!
Thanks anyway.
 

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