Dear ADI
I noticed that some of my simulations made in LTspice 17.0.36, do not work anymore in LTspice 17.1.8.
Al of a sudden it is 'raining' singular martix errors ( if you solve one it will find another) in Spice 17.1.8 when I start the simulation, where the simulation runs fine in 17.0.36. without errors.
What has changed in LTSpice?
I did some investigation, because it seems to happen with conductors with actual .model files attactched to them.
If you create the following simple schematic a single diode with anode floating and only run an operating point analyses; LTspice 17.1.8 will start analysis, completely freezes and than after 15 seconds or so LTspice crahses and closes the program.
If you start the same analysis in Spice 17.0.36 . It wil solve it without any problem.
Se result here:
I know it is not wise to have floating nodes in the circuit., but it is a simple way to show that LTspice 17.1.8 is doing something different than LT Spice 17.0.36 and is less stable operating.
A colleagues has run the same schematic on his PC and it had same result: LTspice 17.1.8 crashes.
(If you connect a capacitor from anode to ground ( value can be anything 1fF will do) . LTspice 17.1.8. will find a solution for the operating point
What has made LTspice 17.1.8 more sensitive ?
Kind regards
Ewold
Hello Mathias,
Thank you for your reply.
I have found the culprit.
For some reason: Enable beta circuit matrix optimizations {*} was checked ON (last check box)
This caused all the problems I had, it also caused the singular matrix errors I encountered
Unchecking this box or turning the option OFF made 17.1.8 behave like the previous version.
You can close the ticket
Kind regards.
Ewold
