Anybody used synopsys 90nm and Encounter together?

Hello all,

I'm trying to synthesize one Sparc core from OpenSPARCT2 with Synopsys 90nm library. **broken link removed**

To synthesize i will use "rsyn spc". After this, I want to do P&R and CTS with Encounter.

Did any of you try to P&R in Encounter with Synopsys 90nm? Even if you did not try this, can you foresee any problem? I think there shouldn't be a problem, but I want to know whether this is feasible before going down the load.

Thank you,

Jinwook

P.S The reason why I want to use this library is that this library have LEFs of Megacells of OpenSPARCT2.

I figured out one problem.

The problem is that I might not be able to export design to Virtuoso Layout for final modification. However, I'm not considering tapping out this. I guess it's fine.

Any of you have an opinion?

Thank you,

Jinwook

Hi,

The problem is that I might not be able to export design to Virtuoso Layout for final modification.

Click to expand...

Why would this be a problem? If you have the gds2 data then you should be fine.

However, transferring data from 1 vendor to another usually has its challenges.


But what you are doing (i.e. transferring RTL data from Synopsys usage to layout in Cadence usage) seems like normal practice in the industry to me.

Best regards,
I-FAB

Hi,

You are correct about GDSII. However exporing GDSII requires mapping file. I think I have to search the library whether they support GDSII map file.

Also, I figured out one more problem. The problem is capacitance table and extraction rules. I think Encounter requires capacitance table for quick timing driven place and route. Also, to run Ostrich to find out the scaling factors, shouldn't we have the extraction realted info?

I want to hear your opinion on this.


Regards,

Jinwook

Captable is important but not required for P&R flow. Generally you can generate the captables using the interconnect information (ICT for cadence and ITF from Synopsys) from the foundry.

The ICT files are downloadable from the foundry. All you need to do is to
download the ICT file and run the following standalone command



Usage: generateCapTbl { -ict <ict_fileName> | -pcs < pcs_fileName>} [-basic | [-solverExe <exec_path>] [-lef <lef_fileName>[-shrinkFactor <value>]]] -output <output fileName> [-bestModel]

Example :
if the ICT file name is tsmc_45nm_cln45gs_1p10m_alrdl_cworst_0.1.ict
then the command will look like this.
generateCapTbl -ict tsmc_45nm_cln45gs_1p10m_alrdl_cworst_0.1.ict -output cworst.captbl


Once the Models are generated then you can use them in your scripts
directly.

for Encounter: Use the following command in the Encounter configuration File
set rda_Input (ui_captbl_file) "cworst.captbl"

For RC Compiler: Use the following command
set_attribute cap_table_file cworst.captbl

---------- Post added at 01:34 PM ---------- Previous post was at 01:32 PM ----------

Similarly for Synopsys P&R you need the ITF file from foundry and here is the method of generating the Captable(called TLU table in sysnopsys Lingo)
The ITF files are downloadable from the Foundry. All you need to do is to
download the ITF file and run the following command

grdgenxo -itf2TLUPlus -I <ITF FILE
if the ITF file name is tsmc_45nm_cln45gs_1p10m_alrdl_cworst_0.1.itf
then the command will look like this.
grdgenxo -itf2TLUPlus -I tsmc_45nm_cln45gs_1p10m_alrdl_cworst_0.1.itf


Once the Models are generated then you can use them in your scripts
directly.

Mapping file should be consistent with the tf file Metal and via name
convention that is provided with the Library. The first column should
be the same name as the tf name and the second column is for the ITF
file. Here is Syntax of the mapping file.
conducting_layers
M1 metal1
M2 metal2
M3 metal3
M4 metal4
M5 metal5
M6 metal6
M7 metal6
M8 metal6
M9 metal6
via_layers
VIA1 via1
VIA2 via2
VIA3 via3
VIA4 via4
VIA5 via5
VIA6 via6
VIA7 via7
VIA8 via8

Hello sohailabbas4,

You are correct. I already aware of that. However synopsys 90nm library does not have Encounter ICT file. It only has synopsys ITF file.
I searched cadence online support, and I found out cadence has a script which can convert ITF into ICT.

Eventhough it might not accurate, i can still use it. After generating ICT file, I can generate captable from the ict.

So the captable problem is solved.

I'm still looking for other possible problems.

Any of you have this kind of experience, just let me know.

Regards,
Jinwook

---------- Post added at 11:56 PM ---------- Previous post was at 11:42 PM ----------

I guess the major problem will be DRC and LVS.

I found one more problem. If the Synopsys 90nm library does not support a signoff quality extraction rules for Calibre or Fire&Ice.
I cannot set the scaling factors in Encounter, because Ostrich requires comparision between a signoff quality RC extraction and captable to figure out the scaling factors.