Hi Everyone!
TLDR: updated QSPICE, broke simulations. Looking for roll back versions.
I had not updated QSPICE for the last 53 or so days (since early Jan 2026) and built some simulations where I was using TI’s opamps (OPA859). I had imported the devices from the PSpice files available on the official website.
Today, when i updated QSPICE, everything broke. The simulations were working earlier in both AC and transient. After the update both, the transient simulations and the ac simulations stopped working.
On further investigation I found the OpAmp models which i had imported had stopped working for some reason. I tried to import the files again but the usual prompt which used to pop up when I dragged a lib file into the schematics did not pop up either.
I want to roll back to the earlier version which I was using, but I am not able to find a version repository/link where I can download earlier versions.
I do not mind if there is a fix which i can do in this version.
Any help is appreciated!
Regards and thanks!
I PM a 2026-Jan-01 version to you.
Can you try to increase your trust level in the forum so that you can upload your schematic for review (method refer to below link)? I saw someone complaining about a TI model not working after a recent update, but after checking multiple TI models in my database, I am not experiencing any issues. Would like to take a look at what you are encountering.
Qspice Forum - New User to Basic User (File Upload) - QSPICE - Qorvo Tech Forum
Sure I will work on increasing the level to be able to share the schematics. Thanks for sharing the roll back file!
I’ll update if it works.
Regards and thanks!
The version you shared works perfectly. In the latest version something must have changed because in the way it is parsing the OPA859 model, which broke the sim.
If I removed just the OPA859, everything else worked. so i am thinking something changed with the parser. It would be amazing if TI started to share SPICE models directly compatible with QPICE and LTSpice.
Anyway, thanks for sharing the older version.
Edit: I’ll attach the sim file once I am able to get my level up.
Please update Qspice to the latest version and verify if the problem is fixed in your schematic. There was an issue with user-parameter evaluation in the subcircuit, and the example I built with OPA859 can now run properly. The update on 30-Jan-2026 was where problem introduced after some optimization to the user-defined parameter.
02/26/2026 Fixed a problem in the peephole optimizer used to evaluate user-defined parameters.
In addition, the failure to copy and paste the subckt library for auto symbol generation is related to improper syntax in OPA859.lib. Its last line is .END, which will end the netlist. Here I upload a modified version.
OPA859-RemoveENDS.lib (14.1 KB)
Symbol in this example is from autogenerated symbol with subcircuit embedded.
example.figure8-1.OPA859.qsch (15.4 KB)
example.sbombq2.OPA859.qsch (17.1 KB)
I had included the explanation about the .END in email which did not go through.
Yes, the original sims are working now. 
Appreciate the quick fix! 
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