Hello, I know this question has been asked a hundred of times, but I still quite can't figure out, what is wrong with my circuit. When I run the simluation I get the error message: Unknown subcircuit called in.. I am still fairly new to LTSpice, so I really hope someone may help. I have upload the schematic to: Temp/LTSpiceAnalogesBackend_upload

I'm a new user, not sure how to get into the Files Section. Is there a model of the LM5117 IC? Thanks

I am creating schematics where the values of several components are calculated parameters, where these values have to appear on the schematic page after a simulation run. Guided by the topic “Showing calc'd Parameter Values on schematic” (https://groups.io/g/LTspice/topic/showing_calc_d_parameter/50270753), at the end I have chosen Andy’s compact solution described in the Temp folder example file <Par_Values_on_Schematic_AI.asc">. Adapted to my schematics, it works just fine. Now, to better understand this method, there are a couple of questions regarding the SPICE Netlist block that implements the useful trick: a) A) What is the logic behind the three lines of the initial “Force .op solution” part?: Dxyz1 xyz 0 Dxyz Dxyz2 xyz 0 Dxyz .model Dxyz D b) B) Why is it a good measure to add 1 GOhm resistors in parallel to all the voltage generators associated to the parameters? rL1 L1 0 1G rL2 L2 0 1G rL3 L3 0 1G …etc Thank you very much and best regards

Hello all, I am simulating a power converter using SiC MOSFETs from Wolfspeed and Nexperia. In both cases, the models are installed properly, but halfway through simulation I get "time step too small" error. Could you please direct me to a thread that addresses this problem. Thank you. Kind regards, Dhara

I've been searching and I can't find a definitive answer, in LTspice and other spices. Referencing this (long) discussion <https://groups.io/g/LTspice/message/135359> from a couple years ago, there may be others, GG.io is not great for following threads. I was wondering if the .TEXT card should work as a way to make it possible to have the location of a library unrelated to the machine it is running on. This is for the purpose of SCM, to allow devs to manage their models libraries, sims etc, in Git rather than haphazardly as is currently done, to avoid the issue of being uable to re-run your or somebody elses sim at some time in the future. Not to mention the issue of random edits and multiple copies on each person's machine. This would also allow continuous integration, e.g. by ensuring filter coeficients are correct. The bigger worry is that in this company, when a person leaves, we have the strage IT policy of simply binning everything in their home and HDD unless they hand it over officially, i.e. actully copying it to another person or shared storage. That means much, especially history LTspice as the files tend to be disorganised are lost. Referencing the above thread, I think the issue with the proposed environment variable is that it's non-portable, and relies on a machine having a particular variable setup for a particular simulation. It would be much better if all the details to construct and re-run the sim are kept in the schematic (or some sort of project file). Now the way I understand it is that the .TEXT card , e.g. .TEXT <var>="Value" ...is like a C macro, in that unlike braces { <code> } the bar | <var> | is only evaluated during elaboration of the circuit. However I tried and a few combinations this with .INCLUDE and .LIB and it seems to just try and open a file with that as it's name, rather than expanding it. e.g. .LIB | libpath | or simply | libpath | being in the model field of the symbol. same with .INCLUDE Tries to open a file litterally called "| libpath |" despite the .TEXT (and also tried a .PARAM for good measure) is in the line above. I could find no documentation on what can be between the bars, except for one example where somebody writes something like | "R" + "5" | . Does that mean that + is a string contatenation. Are there other operators? Is this correct behaviour? or am I using it wrong, is this a bug, or maybe feature request? Secondly, but closely related, is there a way to spawn a shell command from the simulation, e.g. to trigger storage, CI or SCM?. I know only of .FERRET which (though cute and brings back both fond but sad memories) would be complex to use as it would need something to be ferreted. (Though getting single files over https in Git is a thing, expanding a zip of a library would be a problem) Cheers, Jay

Hello, I have to decrypt and modify netlists and I am looking for a work (book or document) on the complete description of the syntax of the spice language. If you know of a reference on the subject, I would like to know it J. In advance, thank you.

Hello, I try to look a bit more in detail at the breakdown region of the diodes, and for that, I am currently using the hand-made model depicted in the Diode_Model_Reverse.asc file uploaded to the Temp folder. It is very basic. What I notice is that the reverse current gradually increases from below 10pA @ 5V to about 100pA @ 99V, before breakdown occurs. I would like to change the characteristic so that current stays at values closer to 0, before the breakdown occurs. So something like 10pA @ 99V. I would be very grateful if you could point me to some meaningful resources describing the extended diode model in this region. Whereas I am able to find some info concerning the BV and IBV parameters, I am completely lacking a good understanding on the effect of the nbv, nbvl, ibvl parameters, and I am also having difficulties in finding a good description of those. Despite that, I have tried changing these parameters (as well as the Is parameter, as a matter of fact) without much impact on the current through the diode when reverse biased at 99V. It seems to be stuck at 100pA @99V no matter what. Regards, Cristian

I was modelling an EDN Design Idea posted a few days ago. Works pretty much as designed, except it defaults to the On state when power is applied. Starting with an initial Push-Hold shuts if off correctly, but I’m looking for suggestions for making it start out Off. Dave

Is there a way to list a search path in a schematic, that is not an absolute path? In other words, can I create a relative search path? Something like using "../.." to indicate up one level from the schematic folder? Thanks! -BobT

Where is the file that Helmut Sennewald refers to in the help file under "exporting waveform data" that is used for manipulating data? "There is also a 3rd party free utility written by Helmut Sennewald. It is available from the independent users' group http://groups.io/g/LTspice(formerly hosted on Yahoo). This utility allows various forms of manipulation of the data including the ability to merge waveforms from different simulation runs."

Hi all, I have a problem with a current regulator that I have designed and wanted to simulate with LTSpice before I build it. Unfortunately it cannot be simulated in closed loop mode (U2 output connected to the 1k resistor next to it) but in open loop (U2 output not connected to the 1k resistor) it works very well. I always get the error message: Singular matrix: check nodes u1:6 and u2:5 Iteration No. 2, I tried several changes with the SPICE control parameters. I only get "ifferent error messages: Either "Time step too small" or "singular matrix". So I expect I do something fundamentally wrong but I have no idea what that could be. Please help. The files I used for the simulations are stored here: https://groups.io/g/LTspice/files/Temp/CurrentRegulator

Hi, I'm using the LMX24_LM2902 spice model, taken from the Texas Instruments website, and it is giving me a lot of issues when simulating my circuits. In particular, it gets stuck when running a transient analysis, sometimes even stopping it altogether. Sometimes it would not even allow me to run the transient. I've tried the same circuit with different Op Amps and it runs smoothly. I've also tried other models for the LM124 I've found in here and they work very nicely. But I'm a bit surprised that my issue comes from a model produced by the manufacturer. Has anyone experienced the same issue before? Thanks! Marcos

Hi, Anyone with the LM124 spice model, could you please share it here, i want to run some SEE simulations. please share

Greetings - I would like to create a generic constant power load to mimic a SMPS effect on a network with diodes, capacitors, supercaps, and such. It would really be cool if limiting behavior of the load could be included (typically current limit) but I can survive without it I am really after macro-scale behavior (like what a capacitor discharge curve looks like with constant power load or what happens to full-wave rectifier ripple levels with constant power loads). If it makes any difference, I am working at milliWatt levels. Any suggestions? Many thanks Jim Wagner, Oregon Research Electronics

Hello Everyone, I’m currently working on simulating a half-bridge circuit using GaN devices from GaN Systems in LTSpice. To generate gate pulses, I’m employing a voltage PWL source to create a double-pulse pattern with varying time durations. At present, I’m using a single resistance for both the turn-on and turn-off phases of the gate drive, but I would like to model separate resistances for each. I understand that this can be accomplished using voltage-controlled switches to selectively route the gate signal through different resistors during the turn-on and turn-off phases. However, I’m having trouble implementing this in LTSpice and would appreciate any guidance or example models that demonstrate how to achieve this configuration. Has anyone successfully set up a similar circuit and can share their approach? Thank you in advance for your help!

Hello all Valve, Tubes or lampes LTSpice users Just to let you know that I have just uploaded a new version of the koren tubes library The major new thing is a approximation of a hexode / heptode model that I have cobbled together The anode response is close but the screen grid is a bit dodgy. Happy simulating Suusi Malcolm-Brown

Please see recent upload… I started from basics. to create a simple log compressor for a limited range of input. That seems to work well in an "ideal" simulation, using Univ OpAmp2. Then I got inspired to test an equally simple DEcompressor by putting the circuit in the feedback path of another UniOpAmp2, which also worked (surprisingly) well. Replacing the amps in the Compressor path with LT1012's appears to work just as desired, as well. But replacing the DEcompressor amps fails miserably. What can I learn today? Dave

I came across this site for sharing LTSpice models: https://youspice.com It seems pretty dated but has a model I'd like to look at, but I wasn't able to get the registration process to complete. Just wonder if anyone knows the status or has the ability to download a model for me? Thanks and 73, Bob W9RAN

Michael Stokowski: Always accept “3k4” notation as 3.4k (no longer optional) Does this mean I will have to accept the DOT madness as used by American engineers ? Goran Finnberg ----Ursprungligt meddelande---- Från : michael.stokowski@... Datum : 2024-11-06 - 18:36 () Till : LTspice@groups.io Ämne : [LTspice] LTspice 24.1 Beta Available Now LTspice 24.1 is beta is available now: https://LTspice.analog.com/download/24.1.0/LTspice64Beta.msi NOTE: As requested by some in this group and elsewhere, the installer installs two executables: LTspice 24.1 Beta and LTspice 24.0.12. There will be icons for both on your desktop. Both LTspice 24.0.12 and 24.1 can be used on the same machine, but don't use both on the same schematics at the same time. What’s New in LTspice 24.1 beta Improved performance and convergence Add .savestate and .loadstate simulator directives to save and restore the complete transient simulation condition Add .option debugtran to add report in log file to help identify convergence challenges Enhanced netlist syntax checking Add support for directory hierarchy for symbol search paths and schematic directory Add support for environment variables in Settings > Search Paths Add "All" symbol directories view in Place Component dialog Changed default integration method to Trapezoidal Remember waveform compression settings (under Settings > Compression) between LTspice invocations Always accept “3k4” notation as 3.4k (no longer optional) Allow device flags to be set to zero for ease of parameterization Updated FRA example fra_eg1 Updated Help documentation Bug fixes -- Michael Stokowski LTspice Team Analog Devices Inc. Best regards, Goran Finnberg The Mastering Room AB Goteborg Sweden E-mail: mastering@... Learn from the mistakes of others, you can never live long enough to make them all yourself. - John Luther (\__/) (='.'=) (")_(") Pyret, Ranglet, Aron, VovVov, Nero, Smurfen & Pussin:RIP

hello, when LTspice was launched in batch mode (command line just with the -b option), how to send (ex : with a python script) an additional command to LTspice for the execution of different netlist files (.net) or schema files (.asc) one after the other ? I would like LTspice not to be stopped and then restarted for each requested run. LTspice should stay in the background keeping the instance alive between calls. In advance, thank you for your answers.