Bootstrap

Working with DSPF Files: Rules for Adding Prefixes to Instance Names

The netlister determines the naming prefix for instances using the namePrefix property set in the Simulation Information section of the Edit CDF form.

The namePrefix for instances is decided as follows:

  • If the namePrefix is not found in the CDF Simulation Information section, the netlister prints X as the namePrefix.
  • If the namePrefix is the same as the first character of the device name, the netlister does not add a prefix to the instance name in the netlist.

If none of these conditions are met, the netlister adds the prefix namePrefix in the output of the instance. You can modify the prefixes that are chosen by either using the dspfNamePrefixSimInfo environment variable or the useSelfCDFInPostLayoutNetlist environment variable.

Examples
  • When the namePrefix and the first character of the device name are the same
    The mimcap device is netlisted in the DSPF as C0, when the simulator used is auCdl.
    C0 outm#64 net044#67 AVSS g45cmim w=5e-06 l=5e-06 m=1 $x=15.29 $y=25.58
     

    Here, the namePrefix in the Edit CDF form is set to C, which is the same as the first character of the device name. According to the pre-defined rules, no prefix is added for mimcap in the DSPF file.
    Setting dspfNamePrefixSimInfo to ams or spectre will add an X prefix and the DSPF will print the device as follows:
    XC0 outm#64 net044#67 AVSS g45cmim w=5e-06 l=5e-06 m=1 $x=15.29 $y=25.58 
  • When namePrefix has no specified value
    Set the dspfNamePrefixSimInfo environment variable to a simulator, such as spectre, that does not have a namePrefix specified for mimcap.

    Based on the namePrefix rules, the X prefix is added to the devices.
    XC0 outm#64 net044#67 AVSS g45cmim w=5e-06 l=5e-06 m=1 $x=15.29 $y=25.58
  • When the device name and namePrefix are different
    Consider that you have resistors in the netlist as shown below:
    R14@2 (net#222 net0178#12 gnd#1330 ) rhim_m lr=3.5e-06 wr=8e-07 + multi=(1) $x=69.656 $y=38.422
    To netlist this correctly with an X prefix, set dspfNamePrefixSimInfo to auCdl because the namePrefix for auCdl is X.

    XR14@2 (net#222 net0178#12 gnd#1330 ) rhim_m lr=3.5e-06 wr=8e-07 + multi=(1) $x=69.656 $y=38.422
    This is applicable in cases when the auCdl prefix is not the same as the first character of the device name.
  • When namePrefix has a value for a specific simulator and none for others
    Consider that a device has the namePrefix set to R for only the auCdl simulator, and no value for other simulators in the Edit CDF form. On netlisting, no prefix will be added to resistors if you set dspfNamePrefixSimInfo to auCdl.

    If you set dspfNamePrefixSimInfo to any other simulator name, the prefix X will be added as per the namePrefix rules.
  • When namePrefix value is not shown
    The namePrefix for mimcap is C for the auCdlauLvs, and hspiceD simulators, and disabled for ams and spectre.

    If you set dspfNamePrefixSimInfo to auCdlauLvs, and hspiceD, no prefix is added, but if you set the environment variable to ams, or spectre, the prefix X is added to the devices.
    XC0 outm#64 net044#67 AVSS g45cmim w=5e-06 l=5e-06 m=1 $x=15.29 $y=25.58
Related Topics

Prefixes in Instance Names in the DSPF File

dspfNamePrefixSimInfo

useSelfCDFInPostLayoutNetlist

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