Tom
02/09/2021, 6:21 AMStefan Schippers
02/09/2021, 9:53 AMschippes@mazinga:~/.xschem/simulations$ ngspice bgr_amp_test.spice
******
** ngspice-34 : Circuit level simulation program
** The U. C. Berkeley CAD Group
** Copyright 1985-1994, Regents of the University of California.
** Copyright 2001-2020, The ngspice team.
** Please get your ngspice manual from <http://ngspice.sourceforge.net/docs.html>
** Please file your bug-reports at <http://ngspice.sourceforge.net/bugrep.html>
** Creation Date: Sat Jan 30 12:16:19 UTC 2021
******
Compatibility modes selected: hs
Circuit: **.subckt bgr_amp_test
Doing analysis at TEMP = 27.000000 and TNOM = 27.000000
Warning: include: has no value, DC 0 assumed
Note: Starting true gmin stepping
Trying gmin = 1.0000E-03 Note: One successful gmin step
Trying gmin = 1.0000E-04 Note: One successful gmin step
Trying gmin = 1.0000E-05 Note: One successful gmin step
Trying gmin = 1.0000E-06 Warning: Further gmin increment
Trying gmin = 5.6234E-06 Note: One successful gmin step
Trying gmin = 2.3714E-06 Note: One successful gmin step
Trying gmin = 6.4938E-07 Warning: Further gmin increment
Trying gmin = 1.7154E-06 Note: One successful gmin step
Trying gmin = 1.0554E-06 Note: One successful gmin step
Trying gmin = 5.0937E-07 Warning: Further gmin increment
Trying gmin = 8.7970E-07 Note: One successful gmin step
Trying gmin = 6.6940E-07 Note: One successful gmin step
Trying gmin = 4.4433E-07 Note: One successful gmin step
Trying gmin = 2.4029E-07 Note: One successful gmin step
Trying gmin = 9.5562E-08 Note: One successful gmin step
Trying gmin = 2.3967E-08 Note: One successful gmin step
Trying gmin = 3.0102E-09 Note: One successful gmin step
Trying gmin = 3.0102E-10 Note: One successful gmin step
Trying gmin = 3.0102E-11 Note: One successful gmin step
Trying gmin = 3.0102E-12 Note: One successful gmin step
Trying gmin = 1.0000E-12 Note: One successful gmin step
Note: True gmin stepping completed
Reference value : 0.00000e+00
No. of Data Rows : 1
Reset re-loads circuit **.subckt bgr_amp_test
...
...
Did you compile ngspice with the 'XSPICE' feature?Tom
02/09/2021, 4:25 PMStefan Schippers
02/09/2021, 4:27 PMTom
02/09/2021, 4:29 PMStefan Schippers
02/09/2021, 4:29 PMTom
02/09/2021, 4:32 PMStefan Schippers
02/09/2021, 4:35 PMTom
02/09/2021, 5:09 PM../configure --with-x --enable-xspice --disable-debug --enable-cider --with-readline=yes --enable-openmp --enable-adms
so it's what you said plus --enable-openmp
as per the section entitled "A fully featured ngspice on LINUX may be obtained with the following commands:".../configure --with-x --enable-xspice --disable-debug --enable-cider --with-readline=yes --enable-adms
as you suggested, removed the {0.5*gain}
expressions and just used 0.5
, and I still get the same error. What is the commit of your build of ngspice? I want to try that next so we're on exactly the same page, and if that fails I'm going to try and boil it down to a simple failing test case.
******
** ngspice-34 : Circuit level simulation program
** The U. C. Berkeley CAD Group
** Copyright 1985-1994, Regents of the University of California.
** Copyright 2001-2020, The ngspice team.
** Please get your ngspice manual from <http://ngspice.sourceforge.net/docs.html>
** Please file your bug-reports at <http://ngspice.sourceforge.net/bugrep.html>
** Creation Date: Tue Feb 9 17:19:56 UTC 2021
******
No compatibility mode selected!
Circuit: **.subckt bgr_amp_test
Scale set to 1e-06
Doing analysis at TEMP = 27.000000 and TNOM = 27.000000
Warning: include: has no value, DC 0 assumed
Warning: singular matrix: check nodes net1 and net1
Note: Starting true gmin stepping
Trying gmin = 1.0000E-03 Warning: singular matrix: check nodes net1 and net1
Warning: Further gmin increment
Trying gmin = 5.6234E-03 Warning: singular matrix: check nodes net1 and net1
Warning: Further gmin increment
Trying gmin = 8.6596E-03 Warning: singular matrix: check nodes net1 and net1
Warning: Further gmin increment
Trying gmin = 9.6466E-03 Warning: singular matrix: check nodes net1 and net1
Warning: Further gmin increment
* single-ended to differential voltage buffer
.subckt sev2diffv vi vc vop von PARAMS: gain=1
EP vop vc vi vc 0.5
EN von vc vi vc -0.5
.ends
279edff5d9877b13ddd7708285553ea20d6f14cd
Stefan Schippers
02/09/2021, 5:32 PMTom
02/09/2021, 5:33 PMStefan Schippers
02/09/2021, 5:35 PMTom
02/09/2021, 5:36 PMStefan Schippers
02/09/2021, 5:36 PMTom
02/09/2021, 5:39 PM******
** ngspice-34 : Circuit level simulation program
** The U. C. Berkeley CAD Group
** Copyright 1985-1994, Regents of the University of California.
** Copyright 2001-2020, The ngspice team.
** Please get your ngspice manual from <http://ngspice.sourceforge.net/docs.html>
** Please file your bug-reports at <http://ngspice.sourceforge.net/bugrep.html>
** Creation Date: Tue Feb 9 17:19:56 UTC 2021
******
Compatibility modes selected: hs
Circuit: **.subckt bgr_amp_test
Scale set to 1e-06
Doing analysis at TEMP = 27.000000 and TNOM = 27.000000
Warning: include: has no value, DC 0 assumed
Warning: singular matrix: check nodes net1 and net1
Note: Starting true gmin stepping
Trying gmin = 1.0000E-03 Warning: singular matrix: check nodes net1 and net1
analoglib
and the sev2diffv
component with the same result. What git hash did you build ngspice from @Stefan Schippers?
******
** ngspice-34 : Circuit level simulation program
** The U. C. Berkeley CAD Group
** Copyright 1985-1994, Regents of the University of California.
** Copyright 2001-2020, The ngspice team.
** Please get your ngspice manual from <http://ngspice.sourceforge.net/docs.html>
** Please file your bug-reports at <http://ngspice.sourceforge.net/bugrep.html>
** Creation Date: Tue Feb 9 17:19:56 UTC 2021
******
Compatibility modes selected: hs
Circuit: **.subckt bgr_amp_test
Scale set to 1e-06
Doing analysis at TEMP = 27.000000 and TNOM = 27.000000
Warning: include: has no value, DC 0 assumed
Warning: singular matrix: check nodes net1 and net1
Note: Starting true gmin stepping
Trying gmin = 1.0000E-03 Warning: singular matrix: check nodes net1 and net1
Stefan Schippers
02/09/2021, 5:52 PMTom
02/09/2021, 6:03 PM.inc
with .include
, so I'm goint to see if that makes my netlist work all of a sudden. What's your theory?.include
with .inc
in your netlist doesn't break it.Stefan Schippers
02/09/2021, 9:02 PMTom
02/10/2021, 1:10 AMlib
statement? since it looks like you don't have that in your version (the passing version) of the netlist but let's see. I'll get back to you with an update shortlyvcomp
pin v1
, and that was the cause of the singularity since the vcomp
pin in the .subckt
definition wasn't actually connected to a subcircuit net as the net in the subcircuit was called v1
. So in the top-level, the cap. was connected to an amp. pin which didn't actually go anywhere in the .subckt
. I just noticed that the ERC info. window actually reports this "short", so I'll be sure to check that next time.
The netlist which was passing was the one with the cap inside the amp. so that was actually a red herring. That's my fault for uploading so many netlists.Amro Tork
03/17/2021, 8:11 AM