4 Replies Latest reply on Nov 26, 2012 10:08 AM by dan_liddell

    help for Perc current density test


      I am facing problem running ESD current density checks.

      is there any difference between LVS rule file and LVS connectivity extraction rule. Because in perc manual it is mentioned that LVS connectivity extraction rule file should be included.

      and for Resistance extraction rule file it is mentioned that callibrated rule file should be given. when i run the test with the available R extraction rule file it gives a syntax error.

        • 1. Re: help for Perc current density test



          You can use the regular LVS deck in a PERC run when netlist extraction is needed.

          Regarding the parasitic extraction, the calibrated deck is recommended, but you can also use RESISTANCE SHEET and RESISTANCE CONNECTION statements.


          Those statements are documented in the SVRF manual, Chapter 4, and you can access it from supportnet:


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          • 2. Re: help for Perc current density test

            thanks for your reply.

            When I run the example test case which is available in the manual, following error comes


            no pin pairs were exported for evalution.




            • 3. Re: help for Perc current density test

              Hi Arshad,


              You can try one of the following:

              1) ADD the puts statment in your rule:
                  perc::export_pin_pair [list lvsTopPort port $dev g]
                  puts "device name is [perc::name $dev]"



              2) cd to "dfmdb/svdb/perc_ldl_data", open file "<PRIMARY>.perc_p2p_pin_pairs" to see the pin pairs.


              If the above does not help, you can open an Service Request on Supportnet.


              Best Regards,

              1 of 1 people found this helpful
              • 4. Re: help for Perc current density test

                I assume you are referring to the Calibre PERC User's Manual, "ESD Current Density Checks" chapter. Assuming that is the case, the following is relevant.


                In the procedure "Running the Calibre PERC CD Flow", Step 2 states you need to set up the appropriate perc::export_pin_pair functions in your rule file. The relevant section of the code includes this:


                  perc::define_net_type "Power"  lvsPower


                  perc::define_net_type "Ground" lvsGround


                  perc::define_net_type "IOPad"  {IN? OUT?}


                This assumes you have LVS POWER NAME and LVS GROUND NAME specified. It also assumes you have top-level ports of the names that match the patterns IN? and OUT?. The ? is a wildcard. If these ports are not in your design, or they are not the ports you want to use, then change their names to what you want.


                  perc::export_pin_pair [list lvsTopPort port $dev g ] -cd


                This command exports top-level ports and the g pins of MOS devices that are on net paths connected to those ports using the net types you specify above. The code also assumes the definition of net path includes paths through resistor devices.


                There are these two lines in the rules from Step 4:


                    set cd_constraint(POLY) "0.2"


                    set cd_constraint(M1) "0.5"


                If you do not have POLY or M1 as layers in your rule file, then you need to change these layer names to what you are using.