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  3. Problems simulating spice netlist in ADE Spectre

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Problems simulating spice netlist in ADE Spectre

MoMiner1870
MoMiner1870 over 10 years ago

Hello all, I recently learned how to generate a spice netlist using QRC extraction.  I am now trying to simulate this netlist using ADE and Spectre.  I can get the simulation to run but the output is not correct.  The layout and schematic simulate correctly using QRC av_extracted view so I know the circuit itself is not the issue.

The circuit is a simple CMOS inverter with one PMOS and one NMOS using the gpdk045 technology.

Here is the spice netlist generated by the QRC process.

*
*                       LINUX           Wed Nov 26 15:20:26 2014
*
*
*
*  PROGRAM  advgen
*
*  Name           : advgen - QRC - (64-bit)
*  Version        : 13.2.0-s329
*  Build Date     : Tue Apr 15 20:11:47 PDT 2014
*
*  HSPICE LIBRARY
*
*
*
*
.SUBCKT inverter gnd! Vin vdd! Vout
*
*
*  caps2d version: 10
*
*       SUBCIRCUIT CALLS
*
XX1/X0 Vin Vout vdd! vdd! g45p1hvt
+ fw=1.2e-07 w=1.2e-07 l=4.5e-08 ad=1.68e-14 as=1.68e-14 pd=5.2e-07 ps=5.2e-07
+ sa=1.4e-07 sb=1.4e-07 sca=86.4917 scb=0.0629898 scc=0.0105661
XX0/X0 Vin Vout gnd! 1 g45n1hvt
+ fw=1.2e-07 w=1.2e-07 l=4.5e-08 ad=1.68e-14 as=1.68e-14 pd=5.2e-07 ps=5.2e-07
+ sa=1.4e-07 sb=1.4e-07 sca=7.40867 scb=0.00452516 scc=4.66241e-05
*
*       CAPACITOR CARDS
*
*
C1    Vin    vdd!    2.63772E-17
C2    Vin    Vout    2.50325E-17
C3    Vin    1    1.33274E-16
C4    Vout    vdd!    2.50555E-17
C5    Vout    1    3.84503E-17
C6    Vin    gnd!    1.0348E-17
C7    vdd!    gnd!    1.86269E-18
C8    Vout    gnd!    2.29578E-17
C9    1    gnd!    4.86107E-17
*
*
.ENDS inverter
*

I then used the CDF editor to create a symbol which I mapped to this spice file.

When I run the simulation I get a few warnings but the simulation does complete without error.

Here are the warnings-

Warning from spectre in `inverter', during circuit read-in.
    WARNING (SFE-2453): The global node `vdd!' and sub circuit terminal `vdd!' will be treated as the sub circuit terminal.

Reading link:  /usr/local/cadence/install/MMSIM131/tools.lnx86/spectre/etc/ahdl/discipline.h
Reading file:  /usr/local/cadence/install/MMSIM131/tools.lnx86/spectre/etc/ahdl/disciplines.vams
Reading link:  /usr/local/cadence/install/MMSIM131/tools.lnx86/spectre/etc/ahdl/constants.h
Reading file:  /usr/local/cadence/install/MMSIM131/tools.lnx86/spectre/etc/ahdl/constants.vams

Warning from spectre in `inverter':`I9', during hierarchy flattening.
    WARNING (SFE-30): "/nethome/users/tesqm2/gpdk/inverter.sp" 26: I9.XX1/X0: `fw' is not a valid parameter for an instance of `g45p1hvt'.  Ignored.

Existing shared object for module bsource_3709ba is up to date.
Installed compiled interface for bsource_3709ba.

Warning from spectre in `inverter':`I9', during hierarchy flattening.
    WARNING (SFE-30): "/nethome/users/tesqm2/gpdk/inverter.sp" 29: I9.XX0/X0: `fw' is not a valid parameter for an instance of `g45n1hvt'.  Ignored.

Time for Elaboration: CPU = 40.102 ms, elapsed = 52.371 ms.
Time accumulated: CPU = 694.231 ms, elapsed = 1.06364 s.
Peak resident memory used = 61.6 Mbytes.

Time for EDB Visiting: CPU = 0 s, elapsed = 1.16897 ms.
Time accumulated: CPU = 694.231 ms, elapsed = 1.06509 s.
Peak resident memory used = 62 Mbytes.


Notice from spectre during topology check.
    No DC path from node `I9.XX1/X0.n1' to ground, Gmin installed to provide path.
Warning from spectre during heuristic topology check - set topcheck=fixall to fix all floating nodes.
    WARNING (SPECTRE-7): No DC path from node `I9.1' to ground.

Does anyone see anything I am doing wrong? Any help would be most appreciated.

Thanks,

Travis Schulze

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