About unbound devices in Assura LVS with IBM cms9flp

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shahriar22nd

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Hellow,
I am checking LVS of a single nfet with Assura in IBM cms9flp. It is an rf type of nfet, which has inherent substrate contact, so I used none explicitly, as can be seen in the attached figure. My problem is, the lvs ends with:

Preprocessing schematic network phase 2
Preprocessing layout network phase 2
*ERROR* Device 'nfet_rf(MOS)' on Schematic is unbound to any Layout device.
*ERROR* Device 'nfet_rf(Generic)' on Layout is unbound to any Schematic device.
*ERROR* UnBound devices found.
Info: All devices must be bound or filtered for comparision to be run.
Exiting nvn.

Would anyone please suggest me what can be done to overcome this probelem?
Thank You
 

Perhaps in the extract.rul file for this technology, that have extractDevice( ) instead of extractMOS() which leads to this specific MOS device get netlisted as a GENERIC device. However, auLVS simInfo in the CDF has this as MOS device, hence schematic side is netlisted as MOS type.

Many remedies:
- use mosDevice in compare.rul - before NVN comparison
or
- use a binding file that has something like

C nfet_rf(MOS) nfet_rf(Generic)

///////
If you want to proceed beyond this error and want LVS to complete anyhow - set :
abortOnUnboundDevices( nil ) --> this is a generic avCompareRules().

In case, the non-english words, commands or keywords above does not make sense, check them inside assura command reference manual.

Hope this helps.
 
Thank you, Sat. I followed the second one- added C nfet_rf(MOS) nfet_rf(Generic) in the binding file and passed the lvs. But, I am thinking why the users have to modify these files! Are we tampering the files and avoiding the actual simulation?
 

I've got the same problem with UMC130nm (both NMOS and PMOS were said to be unbounded). I've written the binding file like this:
C N_12_HSL130E N_12_HSL130E
C P_12_HSL130E P_12_HSL130E

Now I don't get the problem for the NMOS anymore but it still returns error for the PMOS. It says there is no layout cell named P_12_HSL130E. Why did it work out only for the n-type??
Please, help me...
 

I've found out that it worked out for the nmos only because I implemented the pmos with 2 fingers. If I use just 1 finger for the pmos as well, I have no unbound devices anymore. Btw, of course I do want to be able to implement multifinger devices. Do I need a further binding command for them? Should I set up a special configuration in avParameters/avCompareRules?
 

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