Accessing power results from transient analysis in spectremdl

This seems like a bug. I tried using the example in the <SPECTREinstDir>/tools/spectre/examples/MDL_workshop/MDL_workshop.tar.gz - in the "optimize" directory. I adapted it as follows:

//  mvarpwr.mdl
//  (C) 2008 Cadence Design Systems, Inc.
//
// This example is to find optimal values of design parameters 
// by running a multi-parameter, multi-goal search function
//

// alias measurement definition
alias measurement trans {

  // definition of transient analysis with autostop turned on
  run tran( stop=1u, autostop='yes )

     // computation of risetime for signal V(out) from 10% to 90%
     export real rise=risetime(sig=V(out), initval=0.5, \
                      finalval=3.0)

     //computation of falltime for signal V(out) from 90% to 10%
     export real fall=falltime(sig=V(out), initval=3.0, \
                      finalval=0.5)

     export real max_pwr = max(abs(i0.mn0:pwr))

}

// Print results to a specified file beginning with "to=" keyword
print fmt ("\n****Intermediate Results of Optimization Searching****\n\n") to="mvar.print"

// continue to print in user-format with "addto=" keyword
print fmt ("%-15s%-15s%-15s%-15s%-15s\n", "pw","nw","rise","fall","max_pwr") addto="mvar.print"

// workaround - uncomment this and then the power gets properly measured in the subsequent
// mvarsearch (seems like a bug)
//run trans

// definition of a mvarsearch function
mvarsearch {

         // definition of multiple optimization goals
   	 option {
	    //method='lm
   	    accuracy = 1e-3     // convergence tolerance of trans
   	    deltax = 1e-3       // step length
   	    maxiter = 100       // limit to 100 iterations
   	 }

         //  definition of multiple parameters to be optimized
   	 parameter {
   	    {pw, 2u, 0.05u, 10u} //init_val, lower_val, upper_value
   	    {nw, 2u, 0.05u, 10u} //init_val, lower_val, upper_value 
   	 }

         // execution of the measurement alias
   	 exec {
            print fmt("%-15e%-15e", pw, nw) addto="mvar.print"
   	    run trans
            print fmt("%-15e%-15e%-15e\n", trans->rise,trans->fall,trans->max_pwr) \
                      addto="mvar.print"
   	 }

         // definition of goal values to be minimized
   	 zero {
   	    tmp1 = trans->rise-25p
   	    tmp2 = trans->fall-25p 
// uncomment to add this power goal (doesn't work with this alone as the power is always 0)
//	    tmp3 = trans->max_pwr-0.5m
   	 }
}

If I run this:

spectremdl -design invs.scs -batch mvarpwr.mdl

then I get the max_pwr reported as 0 in each simulation and in the summary. Uncommenting the line in the zero section doesn't help - it then finds a different solution but given that the goal is not working, it's not right. I found a workaround by adding a "run trans" (see the comment about a workaround above). Then it works properly and you see the max_pwr appearing in each individual run and in in the resulting optimisation.

I filed a change request (CCR) 2578561 for this. I suggest that you contact customer support and ask for a duplicate to be filed so that it can be associated with a real customer rather than just appearing as an internal request.

Let me know if the workaround works for you too (assuming you're seeing the same problem). I tried with the latest SPECTRE20.1 and 21.1 versions.

Andrew

Hello.

Thank you for your reply. I seem to be able to use this workaround, meanwhile I have asked my admin to file a change request.
I have another problem right here though.

I define my measurement alias exactly as you have, but the log files tell me that the rise time is not found.
Here is exactly how I define my measurement alisas:

```

alias measurement trans {

// definition of transient analysis with autostop turned on
run tran( stop=1u, autostop='yes )

// computation of risetime for signal V(out) from 10% to 90%
export real rise=risetime(sig=V(OUT), initval=0.0, inittype='y, finalval=0.35, finaltype='y, theta1=10, theta2=90)

//computation of falltime for signal V(out) from 90% to 10%
export real fall=falltime(sig=V(OUT), initval=0.35, inittype='y, finalval=0.0, finaltype='y, theta1=90, theta2=10)

export real max_pwr = max(abs(I2.NM0:pwr))

}

```



This is what my input.measure file tells me:
```

Exported variables from results directory: ././input.raw/

date : 8:26:43 PM, Mon Nov 29, 2021
design : // Generated for: spectre
simulator : spectre
version : 19.1.0.396.isr8


Measurement Name : trans
Analysis Type : tran
fall = 1.30558e-07
max_pwr = 4.22013e-08
rise = NaN


Swept Measurements :
Measurement Name : trans-meas_optimize
Analysis Type : tran
fall WP @ 1e-07
WN @ 1.03162e-07 = 1.30742e-07
max_pwr WP @ 1e-07
WN @ 1.03162e-07 = 4.218e-08
rise WP @ 1e-07
WN @ 1.03162e-07 = NaN

```



This is how my test bench is being created, part of the spectre netlist that goes as an input to spectremdl:
```
// View name: schematic
I2 (0 IN OUT net7) char
V0 (IN 0) vsource dc=0 type=pulse val0=0 val1=350m period=100n delay=0 \
rise=100p fall=100p
C0 (OUT 0) capacitor c=20f
V1 (net7 0) vsource dc=350m type=dc
simulatorOptions options psfversion="1.4.0" reltol=1e-3 vabstol=1e-6 \
iabstol=1e-12 temp=27 tnom=27 scalem=1.0 scale=1.0 gmin=1e-12 rforce=1 \
maxnotes=5 maxwarns=5 digits=5 cols=80 pivrel=1e-3 \
sensfile="../psf/sens.output" checklimitdest=psf
tran tran stop=500n write="spectre.ic" writefinal="spectre.fc" \
annotate=status maxiters=5
finalTimeOP info what=oppoint where=rawfile
modelParameter info what=models where=rawfile
element info what=inst where=rawfile
outputParameter info what=output where=rawfile
designParamVals info what=parameters where=rawfile
primitives info what=primitives where=rawfile
subckts info what=subckts where=rawfile
saveOptions options save=all pwr=all
```

I am using SPECTRE 19.1
Can you tell me if I am doing something wrong?

Thanks in advance!


Drop here!

Can you share a plot (in ViVA) of the OUT signal?

Andrew

This is how the waveform looked earlier:



After increasing the period in vpulse, this is how it looks:



This is the updated testbench:

// View name: schematic
I2 (0 IN OUT net7) char
V0 (IN 0) vsource dc=0 type=pulse val0=0 val1=350m period=10u delay=0 \
rise=100p fall=100p
C0 (OUT 0) capacitor c=20f
V1 (net7 0) vsource dc=350m type=dc
simulatorOptions options psfversion="1.4.0" reltol=1e-3 vabstol=1e-6 \
iabstol=1e-12 temp=27 tnom=27 scalem=1.0 scale=1.0 gmin=1e-12 rforce=1 \
maxnotes=5 maxwarns=5 digits=5 cols=80 pivrel=1e-3 \
sensfile="../psf/sens.output" checklimitdest=psf
tran tran stop=20u write="spectre.ic" writefinal="spectre.fc" \
annotate=status maxiters=5
finalTimeOP info what=oppoint where=rawfile
modelParameter info what=models where=rawfile
element info what=inst where=rawfile
outputParameter info what=output where=rawfile
designParamVals info what=parameters where=rawfile
primitives info what=primitives where=rawfile
subckts info what=subckts where=rawfile
saveOptions options save=all pwr=all



This is the entire log file:

Spectre ® Circuit Simulator
Version 19.1.0.396.isr8 64bit -- 19 Jun 2020
Copyright © 1989-2020 Cadence Design Systems, Inc. All rights reserved worldwide. Cadence and Spectre are registered trademarks of Cadence Design Systems, Inc. All others are the property of their respective holders.

Includes RSA BSAFE® Cryptographic or Security Protocol Software from RSA Security, Inc.

User: VLSI_ANALOG Host: cad19 HostID:Hidden PID: 29669
Memory available: 895.8935 MB physical: 3.9327 GB
Linux : Red Hat Enterprise Linux Server release 6.9 (Santiago)
CPU Type: Intel® Core™ i5-2320 CPU @ 3.00GHz
All processors running at 1600.0 MHz
Socket: Processors
0: 0, 1, 2, 3

System load averages (1min, 5min, 15min) : 4.2 %, 3.8 %, 1.5 %

Simulating `./input.scs' on cad19 at 11:51:54 PM, Mon Nov 29, 2021 (process id: 29669).
Current working directory: /home/VLSI_ANALOG/UMC180/Designkits/Cadence_6.1/lowpower28/spectremdl/new
Command line:
/home/installs/SPECTRE191/tools.lnx86/bin/spectre -64 =mdl \
input.mdl ./input.scs

Loading /home/installs/SPECTRE191/tools.lnx86/cmi/lib/64bit/5.0/libinfineon_sh.so ...
Loading /home/installs/SPECTRE191/tools.lnx86/cmi/lib/64bit/5.0/libphilips_o_sh.so ...
Loading /home/installs/SPECTRE191/tools.lnx86/cmi/lib/64bit/5.0/libphilips_sh.so ...
Loading /home/installs/SPECTRE191/tools.lnx86/cmi/lib/64bit/5.0/libsparam_sh.so ...
Loading /home/installs/SPECTRE191/tools.lnx86/cmi/lib/64bit/5.0/libstmodels_sh.so ...
Loading /home/installs/SPECTRE191/tools.lnx86/spectre/lib/64bit/mdl/libSpectreEH_sh.so ...
Reading file: /home/VLSI_ANALOG/UMC180/Designkits/Cadence_6.1/lowpower28/spectremdl/new/input.mdl
Reading file: /home/VLSI_ANALOG/UMC180/Designkits/Cadence_6.1/lowpower28/spectremdl/new/input.scs
Reading file: /home/installs/SPECTRE191/tools.lnx86/spectre/etc/configs/spectre.cfg
Reading file: /home/VLSI_ANALOG/UMCLib/pdk/UMC/28/_G-01-LOGIC_MIXED_MODE28N-HPC/Designkits/Cadence_IC6/G-9FD-LOGIC_MIXED_MODE28N-HPC_UM028FDKHCC0000OA-FDK-Ver.A14_PB/UM028FDKHCC0000OA_A14_DESIGNKIT/UM028FDKHCC0000OA_A14_PB/Models/Spectre/l28hpc_mm_v1201.lib.scs
Reading file: /home/VLSI_ANALOG/UMCLib/pdk/UMC/28/_G-01-LOGIC_MIXED_MODE28N-HPC/Designkits/Cadence_IC6/G-9FD-LOGIC_MIXED_MODE28N-HPC_UM028FDKHCC0000OA-FDK-Ver.A14_PB/UM028FDKHCC0000OA_A14_DESIGNKIT/UM028FDKHCC0000OA_A14_PB/Models/Spectre/l28hpc_rf_v017.lib.scs
Time for NDB Parsing: CPU = 4.75028 s, elapsed = 5.16018 s.
Time accumulated: CPU = 4.90225 s, elapsed = 5.16019 s.
Peak resident memory used = 213 Mbytes.

Warning from spectre during hierarchy flattening.
WARNING (SFE-1131): Scope option `scalefactor' specified with scope `TopCircuit' at line `680' has also been specified at line `729' in file `/home/VLSI_ANALOG/UMCLib/pdk/UMC/28/_G-01-LOGIC_MIXED_MODE28N-HPC/Designkits/Cadence_IC6/G-9FD-LOGIC_MIXED_MODE28N-HPC_UM028FDKHCC0000OA-FDK-Ver.A14_PB/UM028FDKHCC0000OA_A14_DESIGNKIT/UM028FDKHCC0000OA_A14_PB/umc28hpc/../Models/Spectre/l28hpc_rf_v017.lib.scs'. As a result, the last specified value will be used for simulation.

Time for Elaboration: CPU = 71.988 ms, elapsed = 71.0611 ms.
Time accumulated: CPU = 4.97424 s, elapsed = 5.23144 s.
Peak resident memory used = 226 Mbytes.

Warning from spectre during hierarchy flattening.
WARNING (SPECTRE-17101): The value 'psf' specified for the 'checklimitdest' option will no longer be supported in future releases. Use 'spectre -h' to see other recommended values for the 'checklimitdest' option.

Time for EDB Visiting: CPU = 1 ms, elapsed = 952.959 us.
Time accumulated: CPU = 4.97524 s, elapsed = 5.23256 s.
Peak resident memory used = 227 Mbytes.

Global user options:
psfversion = 1.4.0
vabstol = 1e-06
iabstol = 1e-12
temp = 27
gmin = 1e-12
rforce = 1
maxnotes = 5
maxwarns = 5
digits = 5
cols = 80
pivrel = 0.001
sensfile = ../psf/sens.output
checklimitdest = psf
save = all
pwr = all
scalefactor = 0.9
reltol = 0.001
tnom = 27
scalem = 1
scale = 1

Scoped user options:

Circuit inventory:
nodes 3
bsim4 2
capacitor 1
diode 1
vsource 2

Analysis and control statement inventory:
info 7
tran 1

Output statements:
.probe 0
.measure 0
save 0

Time for parsing: CPU = 3 ms, elapsed = 75.556 ms.
Time accumulated: CPU = 4.97824 s, elapsed = 5.30823 s.
Peak resident memory used = 229 Mbytes.

~~~~~~~~~~~~~~~~~~~~~~
Pre-Simulation Summary
~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~

************************************************
Transient Analysis `trans': time = (0 s -> 1 us)
************************************************
DC simulation time: CPU = 1 ms, elapsed = 874.996 us.

Opening the PSFXL file ./input.raw/trans.tran.tran ...
Important parameter values:
start = 0 s
outputstart = 0 s
stop = 1 us
step = 1 ns
maxstep = 20 ns
ic = all
useprevic = no
skipdc = no
reltol = 1e-03
abstol(V) = 1 uV
abstol(I) = 1 pA
temp = 27 C
tnom = 27 C
tempeffects = all
errpreset = moderate
method = traponly
lteratio = 3.5
relref = sigglobal
cmin = 0 F
gmin = 1 pS

Output and IC/nodeset summary:
save 2 (current)
save 10 (voltage)
others 5

Notice from spectre at time = 533.602 ps during transient analysis `trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 963.045 ps during transient analysis `trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 1.82193 ns during transient analysis `trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 3.5397 ns during transient analysis `trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Notice from spectre at time = 6.28397 ns during transient analysis `trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Further occurrences of this notice will be suppressed.

......9......8......7......6......5......4......3......2......1......0
Number of accepted tran steps = 72

Notice from spectre during transient analysis `trans', during task `MDLControl'.
Trapezoidal ringing is detected during tran analysis.
Please use method=trap for better results and performance.

Maximum value achieved for any signal of each quantity:
V: V(I2.PM0:int_d) = 350.7 mV
I: I(V0:p) = 613.3 nA
If your circuit contains signals of the same quantity that are vastly different in size (such as high voltage circuitry combined with low voltage control circuitry), you should consider specifying global option `bin_relref=yes'.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Post-Transient Simulation Summary
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- To further speed up simulation, consider
add ++aps on command line
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

During simulation, the CPU load for active processors is :
0 (5.3 %) 1 (92.2 %) 2 (4.8 %) 3 (2.5 %)
Total: 104.8%
Initial condition solution time: CPU = 1 ms, elapsed = 977.039 us.
Intrinsic tran analysis time: CPU = 15.998 ms, elapsed = 50.0469 ms.

Warning from spectre during transient analysis `trans', during task `MDLControl'.
WARNING (MDL-2034): line `18': risetime - Rise Time Not Found

Total time required for tran analysis `trans': CPU = 21.997 ms, elapsed = 55.702 ms.
Time accumulated: CPU = 5.00624 s, elapsed = 5.37057 s.
Peak resident memory used = 232 Mbytes.

Notice from spectre during task `MDLControl'.
41 notices suppressed.
Warning from spectre.
WARNING (SPECTRE-17101): The value 'psf' specified for the 'checklimitdest' option will no longer be supported in future releases. Use 'spectre -h' to see other recommended values for the 'checklimitdest' option.
WARNING (SPECTRE-17101): The value 'psf' specified for the 'checklimitdest' option will no longer be supported in future releases. Use 'spectre -h' to see other recommended values for the 'checklimitdest' option.

Opening the PSF file ./input.raw/trans.optimize ...

**********************************************************
Transient Analysis `trans-000_trans': time = (0 s -> 1 us)
**********************************************************
DC simulation time: CPU = 1 ms, elapsed = 611.067 us.

Opening the PSFXL file ./input.raw/trans-000_trans.tran.tran ...
Important parameter values:
start = 0 s
outputstart = 0 s
stop = 1 us
step = 1 ns
maxstep = 20 ns
ic = all
useprevic = no
skipdc = no
reltol = 1e-03
abstol(V) = 1 uV
abstol(I) = 1 pA
temp = 27 C
tnom = 27 C
tempeffects = all
errpreset = moderate
method = traponly
lteratio = 3.5
relref = sigglobal
cmin = 0 F
gmin = 1 pS

Output and IC/nodeset summary:
save 2 (current)
save 10 (voltage)
others 5

Notice from spectre at time = 533.602 ps during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 963.045 ps during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 1.82193 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 3.5397 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Notice from spectre at time = 6.28397 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Further occurrences of this notice will be suppressed.

......9......8......7......6......5......4......3......2......1......0
Number of accepted tran steps = 72

Notice from spectre during transient analysis `trans-000_trans', during task `MDLControl'.
Trapezoidal ringing is detected during tran analysis.
Please use method=trap for better results and performance.

Maximum value achieved for any signal of each quantity:
V: V(I2.PM0:int_d) = 350.7 mV
I: I(V0:p) = 613.3 nA
If your circuit contains signals of the same quantity that are vastly different in size (such as high voltage circuitry combined with low voltage control circuitry), you should consider specifying global option `bin_relref=yes'.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Post-Transient Simulation Summary
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- To further speed up simulation, consider
add ++aps on command line
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

During simulation, the CPU load for active processors is :
0 (5.7 %) 1 (90.5 %) 2 (5.0 %) 3 (2.7 %)
Total: 103.9%
Initial condition solution time: CPU = 1 ms, elapsed = 696.898 us.
Intrinsic tran analysis time: CPU = 18.997 ms, elapsed = 46.9458 ms.

Warning from spectre during transient analysis `trans-000_trans', during task `MDLControl'.
WARNING (MDL-2034): line `18': risetime - Rise Time Not Found

Total time required for tran analysis `trans-000_trans': CPU = 22.997 ms, elapsed = 51.2409 ms.
Time accumulated: CPU = 5.07723 s, elapsed = 5.55397 s.
Peak resident memory used = 233 Mbytes.

Notice from spectre during task `MDLControl'.
41 notices suppressed.
Warning from spectre.
WARNING (SPECTRE-17101): The value 'psf' specified for the 'checklimitdest' option will no longer be supported in future releases. Use 'spectre -h' to see other recommended values for the 'checklimitdest' option.

**********************************************************
Transient Analysis `trans-000_trans': time = (0 s -> 1 us)
**********************************************************
DC simulation time: CPU = 0 s, elapsed = 340.939 us.

Opening the PSFXL file ./input.raw/trans-000_trans.tran.tran ...
Important parameter values:
start = 0 s
outputstart = 0 s
stop = 1 us
step = 1 ns
maxstep = 20 ns
ic = all
useprevic = no
skipdc = no
reltol = 1e-03
abstol(V) = 1 uV
abstol(I) = 1 pA
temp = 27 C
tnom = 27 C
tempeffects = all
errpreset = moderate
method = traponly
lteratio = 3.5
relref = sigglobal
cmin = 0 F
gmin = 1 pS

Output and IC/nodeset summary:
save 2 (current)
save 10 (voltage)
others 5

Notice from spectre at time = 533.602 ps during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 963.045 ps during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 1.82193 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 3.5397 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Notice from spectre at time = 6.2846 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Further occurrences of this notice will be suppressed.

......9......8......7......6......5......4......3......2......1......0
Number of accepted tran steps = 72

Notice from spectre during transient analysis `trans-000_trans', during task `MDLControl'.
Trapezoidal ringing is detected during tran analysis.
Please use method=trap for better results and performance.

Maximum value achieved for any signal of each quantity:
V: V(I2.PM0:int_d) = 350.7 mV
I: I(V0:p) = 618.1 nA
If your circuit contains signals of the same quantity that are vastly different in size (such as high voltage circuitry combined with low voltage control circuitry), you should consider specifying global option `bin_relref=yes'.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Post-Transient Simulation Summary
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- To further speed up simulation, consider
add ++aps on command line
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

During simulation, the CPU load for active processors is :
0 (6.0 %) 1 (89.5 %) 2 (5.1 %) 3 (3.2 %)
Total: 103.8%
Initial condition solution time: CPU = 0 s, elapsed = 385.046 us.
Intrinsic tran analysis time: CPU = 14.998 ms, elapsed = 50.4689 ms.

Warning from spectre during transient analysis `trans-000_trans', during task `MDLControl'.
WARNING (MDL-2034): line `18': risetime - Rise Time Not Found

Total time required for tran analysis `trans-000_trans': CPU = 16.997 ms, elapsed = 52.7952 ms.
Time accumulated: CPU = 5.11322 s, elapsed = 5.62573 s.
Peak resident memory used = 233 Mbytes.

Notice from spectre during task `MDLControl'.
41 notices suppressed.
Warning from spectre.
WARNING (SPECTRE-17101): The value 'psf' specified for the 'checklimitdest' option will no longer be supported in future releases. Use 'spectre -h' to see other recommended values for the 'checklimitdest' option.
WARNING (SPECTRE-17101): The value 'psf' specified for the 'checklimitdest' option will no longer be supported in future releases. Use 'spectre -h' to see other recommended values for the 'checklimitdest' option.

**********************************************************
Transient Analysis `trans-000_trans': time = (0 s -> 1 us)
**********************************************************
DC simulation time: CPU = 0 s, elapsed = 352.859 us.

Opening the PSFXL file ./input.raw/trans-000_trans.tran.tran ...
Important parameter values:
start = 0 s
outputstart = 0 s
stop = 1 us
step = 1 ns
maxstep = 20 ns
ic = all
useprevic = no
skipdc = no
reltol = 1e-03
abstol(V) = 1 uV
abstol(I) = 1 pA
temp = 27 C
tnom = 27 C
tempeffects = all
errpreset = moderate
method = traponly
lteratio = 3.5
relref = sigglobal
cmin = 0 F
gmin = 1 pS

Output and IC/nodeset summary:
save 2 (current)
save 10 (voltage)
others 5

Notice from spectre at time = 533.637 ps during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 963.115 ps during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 1.82207 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 3.53998 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Notice from spectre at time = 6.29002 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Further occurrences of this notice will be suppressed.

......9......8......7......6......5......4......3......2......1......0
Number of accepted tran steps = 72

Notice from spectre during transient analysis `trans-000_trans', during task `MDLControl'.
Trapezoidal ringing is detected during tran analysis.
Please use method=trap for better results and performance.

Maximum value achieved for any signal of each quantity:
V: V(I2.PM0:int_d) = 350.7 mV
I: I(V0:p) = 618.9 nA
If your circuit contains signals of the same quantity that are vastly different in size (such as high voltage circuitry combined with low voltage control circuitry), you should consider specifying global option `bin_relref=yes'.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Post-Transient Simulation Summary
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- To further speed up simulation, consider
add ++aps on command line
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

During simulation, the CPU load for active processors is :
0 (5.9 %) 1 (89.3 %) 2 (5.0 %) 3 (3.2 %)
Total: 103.5%
Initial condition solution time: CPU = 0 s, elapsed = 398.874 us.
Intrinsic tran analysis time: CPU = 11.997 ms, elapsed = 43.3631 ms.

Warning from spectre during transient analysis `trans-000_trans', during task `MDLControl'.
WARNING (MDL-2034): line `18': risetime - Rise Time Not Found

Total time required for tran analysis `trans-000_trans': CPU = 14.997 ms, elapsed = 45.732 ms.
Time accumulated: CPU = 5.16421 s, elapsed = 5.70751 s.
Peak resident memory used = 233 Mbytes.

Notice from spectre during task `MDLControl'.
41 notices suppressed.

**********************************************************
Transient Analysis `trans-000_trans': time = (0 s -> 1 us)
**********************************************************
DC simulation time: CPU = 1 ms, elapsed = 353.813 us.

Opening the PSFXL file ./input.raw/trans-000_trans.tran.tran ...
Important parameter values:
start = 0 s
outputstart = 0 s
stop = 1 us
step = 1 ns
maxstep = 20 ns
ic = all
useprevic = no
skipdc = no
reltol = 1e-03
abstol(V) = 1 uV
abstol(I) = 1 pA
temp = 27 C
tnom = 27 C
tempeffects = all
errpreset = moderate
method = traponly
lteratio = 3.5
relref = sigglobal
cmin = 0 F
gmin = 1 pS

Output and IC/nodeset summary:
save 2 (current)
save 10 (voltage)
others 5

Notice from spectre at time = 533.637 ps during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 963.115 ps during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 1.82207 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node I2.NM0:int_s.
Notice from spectre at time = 3.53998 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Notice from spectre at time = 6.29002 ns during transient analysis `trans-000_trans', during task `MDLControl'.
Found trapezoidal ringing on node V0:p.
Further occurrences of this notice will be suppressed.

......9......8......7......6......5......4......3......2......1......0
Number of accepted tran steps = 72

Notice from spectre during transient analysis `trans-000_trans', during task `MDLControl'.
Trapezoidal ringing is detected during tran analysis.
Please use method=trap for better results and performance.

Maximum value achieved for any signal of each quantity:
V: V(I2.PM0:int_d) = 350.7 mV
I: I(V0:p) = 618.9 nA
If your circuit contains signals of the same quantity that are vastly different in size (such as high voltage circuitry combined with low voltage control circuitry), you should consider specifying global option `bin_relref=yes'.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Post-Transient Simulation Summary
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- To further speed up simulation, consider
add ++aps on command line
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

During simulation, the CPU load for active processors is :
0 (6.2 %) 1 (88.7 %) 2 (5.0 %) 3 (3.2 %)
Total: 103.1%
Initial condition solution time: CPU = 1 ms, elapsed = 396.967 us.
Intrinsic tran analysis time: CPU = 17.997 ms, elapsed = 50.3759 ms.

Warning from spectre during transient analysis `trans-000_trans', during task `MDLControl'.
WARNING (MDL-2034): line `18': risetime - Rise Time Not Found

Total time required for tran analysis `trans-000_trans': CPU = 21.996 ms, elapsed = 54.163 ms.
Time accumulated: CPU = 5.18721 s, elapsed = 5.76322 s.
Peak resident memory used = 233 Mbytes.

Notice from spectre during task `MDLControl'.
41 notices suppressed.

Aggregate audit (11:52:00 PM, Mon Nov 29, 2021):
Time used: CPU = 5.32 s, elapsed = 5.96 s, util. = 89.3%.
Time spent in licensing: elapsed = 355 ms, percentage of total = 5.95%.
Peak memory used = 233 Mbytes.
Simulation started at: 11:51:54 PM, Mon Nov 29, 2021, ended at: 11:52:00 PM, Mon Nov 29, 2021, with elapsed time (wall clock): 5.96 s.
spectre completes with 0 errors, 12 warnings, and 36 notices.

Er, this seems kind of obvious. Your transient time is only 1us (the log file shows this, and the MDL earlier shows "run tran( stop=1u, autostop='yes )"). From your ViVA plot and your revised netlist, there's no rise until 5us, so clearly it won't find a rise time after the stop time!

The rise time seems very slow for a 20f load capacitance, but presumably that's your circuit. I suggest changing the stop in the MDL to (say) 20u and then it should work.

Andrew 

Oops! Sorry about that. I did change it in the ADE window and regenerate the netlist, I missed the stop time in the mdl control file.
This works :)

Thank you so much!

Andrew Beckett said:

I filed a change request (CCR) 2578561 for this. I suggest that you contact customer support and ask for a duplicate to be filed so that it can be associated with a real customer rather than just appearing as an internal request.

A quick update - R&D have already fixed this based on my report. I just tested it, and now it works well without needing to have the additional run statement.

The fix will be in SPECTRE21.1 ISR4, which is due out around the 21st January 2022.

Regards,

Andrew