f



Cadence LVS error

Hi,

I am getting an error while running the LVS in Cadence. The error
message says: The inv schematic has changed after it was last
extracted. si: the netlist did not complete successfully.

I had completed a sucessful LVS check on this schematic some time ago.
No suddenly I see this error. I have not modified any schematics/
layout/ extracted layout.

This error is not limited to onr schematic but all the schematics
present in my library. I am not sure how to resolve this issue.

Can someone please hyelp me find solution for this problem? Any help
is really appreciated.

Thank you,
Pallavi

0
pallupat (3)
10/5/2007 5:14:24 PM
comp.cad.cadence 5429 articles. 8 followers. Post Follow

8 Replies
749 Views

Similar Articles

[PageSpeed] 44

On Fri, 5 Oct 2007, pallavi wrote:

> I am getting an error while running the LVS in Cadence. The error
> message says: The inv schematic has changed after it was last
> extracted. si: the netlist did not complete successfully.

The only times I have seen that, the "solution" is to open the schematic 
and do a "check and save" on it.  Further in your post, you mention that 
you made no schematic edits, so I have no idea why the schematics would 
suddenly need to have this done again.  Did you by chance replace, or 
rename a reference library?

I would recomend trying to run LVS on a very small simple schematic, and 
see if the "check and save" works...  If it does, then I have no idea what 
would have caused your entire library to mess up like that.

0
tardis (17)
10/5/2007 6:51:05 PM
On Oct 5, 11:51 am, The Master <tar...@nospam.sdf.lonestar.org.nospam>
wrote:
> On Fri, 5 Oct 2007, pallavi wrote:
> > I am getting an error while running the LVS in Cadence. The error
> > message says: The inv schematic has changed after it was last
> > extracted. si: the netlist did not complete successfully.
>
> The only times I have seen that, the "solution" is to open the schematic
> and do a "check and save" on it.  Further in your post, you mention that
> you made no schematic edits, so I have no idea why the schematics would
> suddenly need to have this done again.  Did you by chance replace, or
> rename a reference library?
>
> I would recomend trying to run LVS on a very small simple schematic, and
> see if the "check and save" works...  If it does, then I have no idea what
> would have caused your entire library to mess up like that.


thanks for replying. I will try 'check and save' option.
I did not change the library name. How do I make sure my entire
library is not messed up? Is there a way to verify that?

If the layout (eg. for a simple Inverter) is 'Flattened', will that
cause this error?

-Pallavi

0
pallupat (3)
10/5/2007 9:17:42 PM
On Oct 6, 7:17 am, pallavi <pallu...@gmail.com> wrote:
> On Oct 5, 11:51 am, The Master <tar...@nospam.sdf.lonestar.org.nospam>
> wrote:
>
> > On Fri, 5 Oct 2007, pallavi wrote:
> > > I am getting an error while running the LVS in Cadence. The error
> > > message says: The inv schematic has changed after it was last
> > > extracted. si: the netlist did not complete successfully.
>
> > The only times I have seen that, the "solution" is to open the schematic
> > and do a "check and save" on it.  Further in your post, you mention that
> > you made no schematic edits, so I have no idea why the schematics would
> > suddenly need to have this done again.  Did you by chance replace, or
> > rename a reference library?
>
> > I would recomend trying to run LVS on a very small simple schematic, and
> > see if the "check and save" works...  If it does, then I have no idea what
> > would have caused your entire library to mess up like that.
>
> thanks for replying. I will try 'check and save' option.
> I did not change the library name. How do I make sure my entire
> library is not messed up? Is there a way to verify that?
>
> If the layout (eg. for a simple Inverter) is 'Flattened', will that
> cause this error?
>
> -Pallavi

'Flatten' won't cause this error. Just click 'save and check' option.

0
mobil787 (30)
10/7/2007 12:51:05 AM
On Fri, 5 Oct 2007, pallavi wrote:

> If the layout (eg. for a simple Inverter) is 'Flattened', will that
> cause this error?

Yes.  The "check and save" is on the schematic side.  It doesn't matter if 
the layout view is used or not, what matters is that the schematic is 
used...

I don't know if there is a skill or menu function to do a "check and save" 
on all schematic views.  If there isn't, the only way is to do it manually 
cell by cell.
0
tardis (17)
10/7/2007 9:52:40 AM
On Oct 7, 2:52 am, The Master <tar...@nospam.sdf.lonestar.org.nospam>
wrote:
> On Fri, 5 Oct 2007, pallavi wrote:
> > If the layout (eg. for a simple Inverter) is 'Flattened', will that
> > cause this error?
>
> Yes.  The "check and save" is on the schematic side.  It doesn't matter if
> the layout view is used or not, what matters is that the schematic is
> used...
>
> I don't know if there is a skill or menu function to do a "check and save"
> on all schematic views.  If there isn't, the only way is to do it manually
> cell by cell.

Hi,

Check and Save option did not help in fixing this issue. It is
something else.
Is there a way I can track timestap on the schematics? That may help
me find what schematic it is referring to during LVS check.

0
pallupat (3)
10/8/2007 6:31:38 PM
> I am getting an error while running the LVS in Cadence. The error
> message says: The inv schematic has changed after it was last
> extracted. si: the netlist did not complete successfully.

> This error is not limited to onr schematic but all the schematics
> present in my library. I am not sure how to resolve this issue.

Is 'inv' your top cell ? It might be due to a change in a child cell, that would explain why the 
error happens with different designs. You can do a hierarchical check/save by choosing 
check->hierarchy in the schematic editor.

Or, it might be the switch/stop view list. Check the content of your .simrc file (or post it)


Cheers,
St�phane
0
10/9/2007 8:10:37 AM
On Mon, 8 Oct 2007, pallavi wrote:

> Check and Save option did not help in fixing this issue. It is
> something else.

Ug...  In that case I have no idea what is wrong.  Like I said, every time 
I have ever seen that error, it was a check and save problem of some 
sort...  It's weird that it didn't help.

Has anyone ever seen that error in cases that didn't apply to "check and 
save"?

0
tardis (17)
10/9/2007 11:26:30 AM
> Has anyone ever seen that error in cases that didn't apply to "check and 
> save"?

Yes : when the netlister ends up with a non-schematic/extracted view which is not in the stop view list.

It figures this must be a schematic of some sort, but since it's lacking the lastSchematicExtraction 
property, it throws this error.

St�phane

0
10/9/2007 12:04:20 PM
Reply: