Ltspice simulation slow. I have a very simple simulation.
- Ltspice simulation slow References. I am trying to simulate the LT8309 being used as a 3-PH AC rectifier. e. LTspice uses waveform compression, so this parameter is of little value and can be omitted or set to zero. Schematic Capture Pcb Design 3D Viewer Gerber Viewer SPICE Hello, I've a doubt regarding how LTspice (or actually any circuit simulator) is able to start the oscillations of an oscillator circuit. And whereas it performs better than single-threaded, it's not the best out there in terms of performance, but it's free. 6. Regards, Heisenberg Could you tell me if you have changed any simulate settings in LTSpice? I suspect I have to change some of my settings in the software, as I stay all the settings default at the moment. If anyone knows of a free or even not too expensive Spice-based simulator that is faster than LTSpice, I'm interested Hi everyone, I have a problem with transient simulation on LTSpice. I have successfully simulated op-amps and their related circuitry individually, but when I put them together into one OK, they were slow on my laptop and on my old computer. L. The sim runs very slow and says: "Stepping Source 100% step size=8. 3V, no resistor, rectifying diodes that are too slow for the switching frequency, a filtering cap with no series resistance, and a load that may as well be open air. I tried to simalate a pretty simple schematic: R2,R3 and R4 resistors are for solve floating node problem. This helps in many cases. Generally, the simulation of switching On some simulations, LTspice runs verrrrrrrrry slowly. Removing the maximum will allow the simulation to run at variable timestep. When I simulate the circutio composed of a single OpAmp I have no problems. Nochmals vielen vielen Dank für den Tipp! Einen kleinen Unterschied zwischen LT317A / LM317 und dem I have a brand new 6th generation i7 laptop with 16G RAM. Problems arise when I create a chain with at least 3/4 devices in series with transients reaching 95/ 1. The simulation itself is a small-ish sized simulation of a DC DC converter, pretty much the test jig for the device, only with saturable inductors (I'm not sure I've done them properly) and a second filter - basically I was just messing around. Otherwise, it never completes. With Cload >= 1nF, circuit is very slow to simulate, sometimes it will do the job, other times it gets stuck in pseudo transient analysis. operational-amplifier; ltspice; Share. Yet, the Now my problem is that the simulation is very slow. When I simulate, I will run the simulation and when it is finished, I will click on a node/component lead in the schematic to see a voltage/current. 01 to 1. Würth Elektronik. Ultimately the problem is that this design has significant oscillation, likely due to the large inductor. Download LTspice; LTSpice IV Getting Started Guide; The LTSPICE IV Simulator, Reference Guide, Gilles Brocard. A calculation I made with another user's i7 (who kindly tested the circuit) does it in a minute. To Insert or Edit a Simulation Command: Choose Edit Simulation Cmd from the Simulate menu. Am I (see screenshot)? Would someone mind pointing above SCR. Hello, I'm using a third party model file (from TI) for a buck converter. Sometimes, it has to be skipped manually by hitting the Esc button. The first step is the calculation of the DC initial solution shorting the inductors and opening the capacitors inside The thing is, when I run the simulation the "delayed" signal is not really delayed --- it is an exact copy of the signal at the input of the first delay flip-flop. (It PyLTSpice is a toolchain of Python utilities designed to interact with LTSpice and NGSpice Electronic Simulator. XSpice is ngspice like with multi threaded and shared processes possibilities to speed up simulations. Currently, the simulation is taking a very very long time. Because the . Below are resources organized to help you get started or perform more advanced LTspice simulations. Perhaps most everyone attempting simulation in Kicad finds both success and shortcomings with NGspice I’ve had the various success’s and shortcoming’s and prefer LTspice but, I often want to do the schematic in Kicad - thus, I compromise, as follows: I export a Netlist from Kicad and use it in LTspice and Run LTspice directly from Kicad. io? This cannot be undone. AC, transient and noise I've been using LTSPICE for a while but still have a lot to learn. The LT1920 completes in under 1 second and is accurate, ie a 2v Pk-Pk input signal in green is multiplied by 2 and output in blue. options). Compared to other simulation tools, PSpice takes more time to finish simulations. I'm not in the same room with an LTSpice application, but AFAIK it uses a Runga-Kutta solver, which doesn't do well with stiff systems (Google "stiff system simulation" for details). > > Best Regards > George > > > Hell Hello, You could try the advice given in the FAQ. I've uploaded to the temp directory This makes DC sources to ramp up in a fraction of the total simulation time (10 us, IIRC). This is true when the Li-Ion_Batt (U1) components is missing. PVakrani117 on May 13, 2019 . The ISO16750-2 and ISO7637-2 symbols in LTspice provide simulation models of the transients described by the ISO 7637-2 and ISO 16750-2 specifications. What's I've been using LTSPICE for a while but still have a lot to learn. cir it can be loaded into LTspice and simulation run. Shouldn't the leakage inductance be in parallel to the coils. Feeding the The MOSIS design service can supply TSMC SPICE models as part of a complete design kit. Attachments. One option is to simplify your circuit design by removing unnecessary components or simplifying I am running a simulation on LTSpice. However, there is a problem with the simulation. ASC, as this is just a very preliminary check of the models and simulation. It was only marginally quicker then just finding the poles and zeros by hand. The simulation runs though Any ideas? Thanks . Use a resistor in series with the BOOST pin (between the flying cap and the BOOST pin) for a more effective solution. × Close Verify Delete Are you sure you wish to delete this message from the message archives of LTspice@groups. I have a very simple simulation. Change the capacitor back to 10nF, and run the simulation again. I'm not saying there aren't other problems. They may also have a I am not using Windows 11 --But LTspice XVII on my laptop is also rather slow when painting the full 2 seconds of the simulation in the plot window. zip This simulation was a little bit faster with the options Hello, I've a doubt regarding how LTspice (or actually any circuit simulator) is able to start the oscillations of an oscillator circuit. It includes tabs for each HMM, the same SLOW sim time was back! This, to me suggests that my circuit is most likely OK. Does anyone have any suggestions on what can be done to fix this problem with the simulation not progressing? More. If your simulation stalls on occasion, then bumps along just fine for a while, then stalls again, look for a node that may be ringing from a sudden change. Anticipate EMC with LTSpice Using LTSPICE and Redexpert to check power supply designs TA_Master2020A_Agenda0_0 Intro : From functional simulation Output ripple of a Buck Extracting EMC accurate data from REDEXPERT Example of (non) EMC accurate impact on simulation To EMC simulation Enabling EMC measurement in LTSpice Inductors are pillars among electronic components. You must carefully adjust their values and watch what effects they have on the Signal chain LTspice simulation guide Precision wide-bandwidth current or voltage measurement, density optimized Introduction For this implementation of the signal chain, we This guide offers a walkthrough on simulating a precision wide bandwidth measurement signal chain optimized for density, using the accompanying LTspice schematic (. 13. He knows to not run anything else, we've pared down his machine so it doesn't have a bunch of crapware on it, etc. So I dumped it into a project but the simulation gets stuck. Lossy Cables (e. Since I am in the initial phase of the Hi All I have setup a simulation in LTSpice with components selected that I wish to create a real PCB for but wanted to simulate it first, I wondered if anyone wouldn't mind looking at it and making any suggestions of how I could improve this. I have used LTspice XVII. Gootee . How to speed up the simulation with LTspice, I try with simple DC/DC converter but it takes really long ? 37dcto3v3. And I needed to use the startup setting. STEP param DeviceName list 1 2 3. If the FET and diodes have low 'on' resistance then the Second, try changing the solver. Add initial conditions. No problem there, that's a complexity issue or component parameter choice or whatever. asc and any libs, etc. Keep this in mind if you answer this message. Option settings defined in the SPICE PCB Layout , EDA & Simulations LTspice runs very slow problem Home. Before I build and try I decided to simulate it in LTspice as follows: I'm stuck at point about modelling the loop antenna for the simulation. If anyone could give me some tips on how to speed it up, I'd appreciate it. The exercises are meant to be done I've seen other messages related to slow simulations and the heightened def con messages, and I've tried adjusting Gmin, and Trtol, and I've switched to using the alternate solver, but nothing seems to improve the slow simulation. I picked up the models from the LTspice Files The simulation also runs very slowly and often fails to converge at some point. Theoretically I would expect in out an impulse of 20 usec, instead at the arrival of the CK the output (OUT) goes high and stays there. Thanks for the quick feedback guys - much appreciated. This circuit obviously does the job. How to improve Electronics: ltspice simulations is so slowHelpful? Please support me on Patreon: https://www. Download the latest version of LTspice from their website to try out the simulations. The waveform window worked fine this morning and then I went on to build the colpitts oscillator ( please see the attachment) and ever since I cannot see the waveform windows. The file name is spice. It employs a powerful simulation engine capable of handling both transient and steady-state analyses. If you used Simulate > Pause (or ctrl-P), then you can resume it AD620A and B: Slow simulation speed Thomas P. When simulation is run pressing ESC skips the pseudo analysis and a Use LTspice's option dialog and fiddle with the simulation engine parameters in the SPICE tab. 5. DC Operating Point ðlThis is a simple, but incredibly useful analysis. A typical simulation takes about 2-4 seconds. Figure 1. 7 Before diving into the simulation process, ensure you have: LTspice Installed: Download and install the latest version of LTspice from Analog Devices using this link. It includes tabs for each Because one of them has multiple net names, LTspice uses "DC_DC_IN" as the net name that it refers to. If it needs to be small, then it needs to be small. When circuit variables (node voltages, for example) are changing rapidly, it will take shorter Subject: [LTspice] REALLY slow simulation (op-amps) I've been working on simulating a circuit for noise and offset. Interesting detail - it is enough to replace a BC capacity by a real capacity (I tried with BCqp ) and the simulation runs much faster Sometimes the simulator cannot find a DC operating point before starting the transient simulation. Someone can you explain why it doesn't work properly? Signal chain LTspice simulation guide Precision wide-bandwidth current or voltage measurement, density optimized Introduction For this implementation of the signal chain, we This guide offers a walkthrough on simulating a precision wide bandwidth measurement signal chain optimized for density, using the accompanying LTspice schematic (. I can only simulate 10ms and it takes about 10 minutes to complete. zip Slow simulation on LTspice. And when I wanted to simulate the short, I put the resitor at 1 mohm. You shouldn't need to change anything in the op-amp's properties, but looking at them will give you a hint of some of LTSpice's more advanced features. com/roelvandepaarWith thanks & praise to God, and with FAQ: My LTSpice simulation is too slow Why is my LTSpice simulation running so slowly? There could be several reasons why your LTSpice simulation is running slowly. 0. The simulation run even more slowly without R3 and R4 (both are 10G). When I simulate in SPICE I find it produces a ramp between 1-3V and a cannot force it negative. 4 ms, when using the AD8422 or AD8221 (probably also with other amps of this type) in the following configuration, which is to my understanding an allowed operation state: When you hit escape during a stalled DC simulation in LTSpice, the simulator progresses to the next solution method. But if PCB Layout , EDA & Simulations: 3: Jul 1, 2024: Buck Converter Simulation in Python: PCB Layout , EDA & Simulations: 0: Jun 21, 2023: J: Huge Input Current Spike Buck-Boost Converter LTspice simulation (example design exported from LTPowerCAD) PCB Layout , EDA & Simulations: 10: Nov 8, 2022: A: buck converter simulation, some insights and How to trace down why LTSpice simulation is slow? 3. And CPU does not even get loaded, it JJ wrote, "step size = 3. I think the software is so slow or so complex LTspice includes simulation commands for transient, linearized small signal ac, dc sweep, noise, dc operating point, and small signal dc transfer function analysis. 1e-3. It is a remote controller, and I know much probably there's a better way to do it, but I only can use this component: voltage switch, capacitor, inductor, current source controlled by voltage, transistor, resistor,in other words, basic components. OPTION” command allows you to change the parameters not displayed in the panel, including “itl1” and “itl2”. param Nch DeviceName. \$\endgroup\$ – Nonetheless, we would like to help you so can continue to use LTspice in your projects. patreon. Open the . Thanks All. 5 V, across the load resistor (plus some ripple). Perfekt. asked Jun 29, 2020 at 21:29. So I thought that, after all, LTspice wasn't that bad. I would recommend changing your design When he's running LTSpice, some simulations take a while. The description of the file is Slow Simulation after 4. mosis. ac) DC Sweep Analysis(. However, when voltage on the Sink goes above 25V, simulation speed slows dramatically (from 500ks/s to 2ms/s). Here's my netlist: R1 Vout_man V1 1k R2 Vauto N003 220k C1 N003 0 47n V1 5V 0 5V V2 /Vpor 0 5V V3 Vswitch 0 PWL(100m 0 100. Depending on your criteria, you can speed up the simulation time. 2. Open or Short Circuit at Cable’s End 88 13. Loading the complete model it spends forever in the stepping phase, then pseudo-damped NOTE: this is not LTspice but how spice simulators run in general. If I still can't get it to perform well, I can work on a transformer "simulator" to use in the test circuit. As a designer you 1. LTspice ® Technical Information and Guides. LTspice Transient Simulation with external components. The second is when a short happens. meas command: unexpected single fail in step when the rest passes ok. Obviously, this is not a good idea. Follow edited Jun 28, 2019 at 16:23. Schematic Capture Pcb Design 3D Viewer Gerber Viewer SPICE I cannot see the waveform output window during simulation in LTspice IV. I can not simulate correct operation of the 74HC123 retriggerable multivibrator. asc . Joined Mar 13, 2023 10. I added a 1 ohm series resistance in the 3800u to get a faster simulation? Or perhaps anything else? Thank you and sorry for my english :)) regards micha Hello Micha, The simulation speed depends on the circuit size, the complexity of the models and the "activity" of the node voltages. Fast-Fast, Slow-Fast etc. My hacked INA138 to INA139 file is working, though slow as hell. Transient Analysis(. Clearly, the effort spent in simulation I'm running 64 concurrent simulations of LTSpice using Wine on a 64-core Centos linux machine to acquire ideally several million data points. I did notice that the model for the 2197 is a lot more complex than the other installed LT/AD models. The one most relevant to your needs appears to be sim_batch. None of the equations I tried gave me Your simulation command (. My simulation runs very slowly when simulating a single-phase half-bridge inverter with IGBTs. Simulating protection circuitry during the design phase of product development helps to avoid failures that would otherwise occur during the EMC testing of hardware. LTspice . Especially source stepping can be omitted with ". I assume that a simple transformer is considered to be relatively ideal in LTSpice. Refer to the help file for further information. Forums. What can I do to make this run better? 1106. Transient analyses always start at time equal to zero. I can't upload my circuit model for some reason. Its a simple circuit, copied from the LT1920 version alongside. Is there a way to I am having some trouble with the SPICE model in LT SPICE. However, be aware Slow Digital Simulation - Damped Pseudo Analysis Problem; × Close Search Search Cancel Date Date 1 If the above text is saved as demo. At first I was just putting a resistor at the output of my circuit to simulate my load. Download link to all required LTspice files: Simulation. So I set ". However, if Tstart is specified, the waveform data between zero and Tstart is not saved. Slow Digital Simulation - Damped Pseudo Analysis Problem; × Close Search Search Cancel Date Date 1 If the above text is saved as demo. 2MHz as like LMR50410) and the simulation takes 30 seconds (2. When I want to do it over and over again (trying out It is found that the speed of simulation is very slow, and the transient simulation of 10ms takes half an hour. This makes DC sources to ramp up in a fraction of the total simulation time (10 us, IIRC). In particular, you can use the alternate solver, which is slower but have higher internal accuracy, which could make some simulations converge. Basic Understanding of AC Circuits: Familiarity with RLC circuits, resonance, and bandpass filter behavior will be helpful. As you can imagine I'm a beginner with LTspice. I don't think my laptop is the problem. Your I'm trying to simulate two scenarios in LTspice. Basically this circuit is using a floating ground with an lm8261. You might want to enter a sine signal there, though. Is there a way to high-frequency oscillations ("ringing") can cause outrageously slow simulations. Should look something like this: OK, they were slow on my laptop and on my old computer. All Messages By This Member #10012 Does anyone have any ideas that might help to speed up simulations that include the Analog Devices spice model of either the AD620A or AD620B instrumentation amplifier? I want to try using one to replace a differential opamp configuration in an existing simulation. The circuit in question has several weak spots regarding convergence (the worst one being sensing current with a resistor instead of a zero volt source), but these are not the root cause of the consistency problem. 001m 0 250m 0 Peculiar circuit configurations (such as trying to PWM a large capacitor) can also make the simulation slow. Reply Cancel Cancel; 0 rs2322 on Jul 1, 2024 7:42 AM solved, added some load and now it run really fast :) Cancel; Up 0 Here is the simple approach to simulate a transformer in LTspice IV: Draft an inductor for each transformer winding; Couple them using a single mutual inductance (K) statement via a SPICE directive: K1 L1 L2 L3 1. Hi, I am trying to do a transient analysis of the below attached circuit but it never stops running. High frequency ringing for example can make a simulation very slow. com> Sent: Wed, November 2, 2011 12:11:30 PM Subject: Re: [LTspice] Re: Slow Transmission line simulation A leakage inductance of 3. The slow ramp on the GATE results in MOSFET heating, but it is not yet in current limit where the LTC4260 timer starts to run. Is there any option that I could use to speed it up? Or, I made some mistake in the simulation? 2. Best regards, Helmut. options cshunt=1e-18 I don't recommend higher values for cshunt, because this model contains capacitors with only 1e-15 Farad. What I came up with, is for example. How can I make the simulation faster? I use LTspice and I made similar simulation using LT3502 (it works at 2. The simulation of 19 transistors and 4 op amps in nested feedback loops took 5 to 10 days to run on a dual core 3GHz Most probably, your simulation takes so much time due to convergence issues. For these, the solver found a solution. Simulation Commands A. Simulations on reasonable-sized circuits run quickly and without a hitch, when I am in the office, connected to our Corporate LAN. Only the last 100us are interesting for me. In some cases, changing these tolerances may be the only way to get a simulation to run at all. Please, could someone review the simulation and provide some guidance on the best way to improve the simulation time You will see that the maximum temperature of the MOSFET is now over 300°C when the load is 1 ohm. Cedric. The FDZ294N model from the same website runs fine and I notice it does Simulation of the Example with LTspice 85 13. Like Reply. The main output to plot (ctrl-A) is V(output) to see a squarewave. I just want to check this out for one half-cycle using the above SCR. I ran simulation in parallel to speed up the process. In fact, at lower I have a customer who is currently using LTSpice and experiencing a significant slow-down in runtime of their simulation due to the TPS61170 LTSpice part. The model file is an unencrypted file, however when I'm using it in the simulation it says "Ignoring empty pin current" and the simulation doesn't converge. I can use a voltage sources with reasonable resistances, to drive the tube rectifier. It models ON resistance and gate charge accurately, but pretty much ignores many of the other parameters in an effort to get the simulation to work fast. Basically the circuit (simulator) has to take timesteps small enough to properly model the carrier frequency (say 100 MHz), while also running long enough for your modulation to progress through a few cycles. I guess 40us/sec on When I was doing DC sweep for bias voltage of the tail transistor, the simulation was very very slow. Apr 5, 2023 #7 crutschow said: Below is the sim, which did not stop. When I want to do it over and over again (trying out various component values) it takes to much time and it's annoying. The simulation is computing 10ns worth of data a time. The Edit Simulation Command dialogue will appear (Figure 10). It seem that stopping the Another option is to partition the simulation interval [0, Tstop] to sub-intervals of fast-changing and relatively-slow-changing values, but it requires an effort sometimes equivalent to manual processing of simulation data. com. dc) Noise Analysis(. g. Look at the Tc-FET LTspice-Simulation Commands Setting 2022 12/11. Reply Cancel Cancel; 0 rs2322 on Jul 1, 2024 7:42 AM solved, added some load and now it run really fast :) Cancel; Up 0 KiCad integrates the open source spice simulator ngspice to provide simulation capability in graphical form through integration with the Schematic Editor. Or the increment is too small (1u second). Before diving into the simulation process, ensure you have: LTspice Installed: Download and install the latest version of LTspice from Analog Devices using this link. I set it to 25, but feel free to set it to 100, or something else. For practical circuits, it LTspice recommends starting with a mutual coupling coefficient equal to 1 in order to eliminate leakage inductance that can ring at extremely high frequencies (if damping is not supplied) and slow the simulation. Relative ratio between the largest column entry Hi, I have a LTSpice circuit simulation using three (3) SW switch models. STEP directive requires numeric arguments, you will need to change the model names to The steady state point is a special feature of LTSpice for SMPS simulation, but not suited for all kind of circuits. Circuit Schematic Ready: We’ll use an RLC circuit as our example. We may be able to help you if you can upload here your simulation *. There's some flexibility here. lib LED_TRIAC_ZCS. Model "elen254n": Oxide thickness thinner than recommended for a level 3 MOSFET. But I'd like to "automate I think that LTSpice needs some sort of reference in order to tell you what is the voltage between some point on the primary and ground. If instead you Halted it (by clicking the hand toolbar button, or going to Simulate > Halt, or right-click then Halt, or ctrl-H). There is a speed option in the simulation setting window and the default value is 3 and I left it 3. I was expecting to see approximately 24 * sqrt(2) - 2 * 0. (I'll The LTspice simulation model predicts the actual lab emissions’ major peaks with excellent accuracy. It might make your simulation run faster by giving you incorrect results faster. asc Thanks Hello, The simulation runs quite normal. AD620A and B: Slow simulation speed Thomas P. I've had a bit more of a play around with the circuit and I think the source Another option is to partition the simulation interval [0, Tstop] to sub-intervals of fast-changing and relatively-slow-changing values, but it requires an effort sometimes equivalent to manual processing of simulation data. Hardware Design. com; muhammad <mmuj2000@yahoo. LTSpice: How to offset the start time in a transient simulation? 6. Our updated schematic will eventually look like the one shown below. Prerequisites. asy TYN640. Your signal sources are also 0V in a transient simulation, but that shouldn't prevent LTSpice from simulating it in the first place. Excerpt from its description: This module is used to launch LTSPice simulations. Charly Huang. I have tried with changing to Alternate Solver and setting the Reltol to 0. 99896e-05. LTSpice is installed locally on my laptop, and the . One common reason is that your circuit design is too complex, and the program is having trouble processing all the components and calculations. Unusually hot MOSFET: 70w mosfet at 1kw out. ? cheers AG KiCad integrates the open source spice simulator ngspice to provide simulation capability in graphical form through integration with the Schematic Editor. . Your mileage may vary. In addition, the “. This example uses the LT3757 test fixture as a starting point. 5uS it really slows Our circuit is looking good, but to run a simulation, we need to add power supplies and let LTspice know what type of simulation we want to perform. tran) AC Analysis(. I'm in the low 10s of ns/s speed range. One is when things are ok. One way to do this is: In the schematic, rename the N and P devices to {Nch} and {Pch}. How can I simulate a RG58 Coaxial Cable? 90 13. 65 (diode drop) = 32. Feeding the . My simulation is running so slow (it can take a day) and It depends entirely on the models used and the settings in your simulator. py. Can anyone please Yes -- but only if you had Paused the simulation. 75 mhenry in series with a 4 henry inductance gets swamped. Figure 17. op point. What's I'm new to ltspice so I thought I'd run a simple simulation up through the rectifier and filters. Am I doing something wrong here? I have seen other people produce sine waves using LTSpice, so I'm pretty sure it's possible. As Alec suggests, I strongly recommend you use the LTspice models. 9e-5, it takes a long time and doesn't plot anything " The step size (if that's what you really meant to write) is whatever it has to be. For some reason simulation of just 20 ms turns into about 15 seconds to accomplish. As a remedy to this situation, I recommend you to have what the simulator gives to you and postprocess this data to any form you like with a program, I'm using LTspice to simulate a simple rectifier circuit using a sine wave generator (24 V, 50 Hz), a full wave diode bridge, a reservoir capacitor (2200 µF) and a load resistor (1k). HTH, Donald. What's wrong with the model? Can it be fixed? It's an Orcad model from Fairchild website. 001m 0 250m 0 I cannot see the waveform output window during simulation in LTspice IV. Advanced simulation capabilities are another key strength of LTspice. PCB Layout , EDA & Simulations. Personally, I haven't found many cases where an 8/16 CPU feelt slow, and using a cluster for computing may imply having extremely complicated schematics LTspice@groups. On the output of the LTC6990 circuit there is a frequency modulated signal. AC, transient and noise LTSpice simulation of rectifier slows down after short time. A set of simple simulation exercises to start using LTspice. But internally, LTspice keeps track of both names. Usually TI Pspice models are unstable in LTspice. Our OPA197macro-model is much Our circuit is looking good, but to run a simulation, we need to add power supplies and let LTspice know what type of simulation we want to perform. This way, the beginning of the simulation will see the supply voltage at t=0 as 0 V, thus the capacitor will also start from zero. 001m 1 120m 1 120. But In LTspice if I run the simulation for the first 250ms I obtain this plot where Vout < Vin: a FET driven directly by a voltage source, with 3. I would suggest to Hi, I can't simulate when importing a simulation model; it says there is a mismatch regarding the pins. tran 1 with no other parameters. That way, I can get the effects of the tube rectifier, without the hassle of the transformer. Since I am in the initial phase of the design, I would like to have a faster simulation instead of an accurate one. You can modify the mentioned parameters, and compare it with a "good" result which takes 2 hours siumlation time. This will force the solver to consider a custom value for the voltage at that node. My favorite go-to in this case is the Gear solver. zip-----I uploaded also a standard test circuit. Through this tutorial, you will learn how to perform transient analysis to observe how a circuit responds over time, making it ideal for studying transient phenomena like start-up behavior and signal I uploaded a file for some analysis I am trying to run in LTSpice. options cshunt=1p I am having very slow and somewhat erratic simulation recently. While building the circuit, I encountered the following problem: the simulation of the circuit is particularly slow at a certain moment (denoted as t), about tens of μs/s. And CPU does not even get loaded, it LTspice XVII I'm adding again the TI simulation as a ZIP file, updated. Pick one with a similar VDS, QG and RDSON to the one you intend to However the simulation takes almost 30 mins to complete and is inaccurate, as can be seen below. But now I have a 4 core APU (3,7 - 4,2 GHz), and simulations are still slow. It needs 4000us to load the capacitors an get a stable condition. buck closed-loop. This simple setup should be fine, however. There are more to say but that's about as much as I'll go based on your lack of input. Schematic For Simulation. 3. 12. I have several theories: The schematic is complicated, To maintain fast simulation speed, LTspice uses a compressed binary file format that allows additional simulation data to be quickly appended on the fly. There may be a flaw in the LTspice IC model. 5. LTspice runs very slow problem . Hot Network Questions Handling a customer that is contacting my subordinates on LinkedIn demanding a refund (already given)? Bitcoin Core Development How to determine what is opening tmp files when I invoke a subshell with ksh In general relativity, how do we know when the coordinates we compute are physical LTspice uses a simplified model for all of its MOSFETs. He's sadly stuck with Win11 since the Ah, yes, I tried to use Tina-TI: it looks nice, but I couldn't even find a way to get a simple graph of an arbitrary voltage node after the simulation had run. The settings you are trying to change refer to the Transient Analysis simulation time. 1. LTSpice transient I wondered whether theory matches practice so I tried to simulate the circuit in LTSpice. The first step is the calculation of the DC initial solution shorting the inductors and opening the capacitors inside Hi, I have a LTSpice circuit simulation using three (3) SW switch models. cir file provided by the Analog site. It was so slow I even pulled out my old laptop with 4th generation i5 and 8G RAM. Files > FAQ > faq_10. Cancel Yes × Close Verify Repost Are you sure you wish to repost this message? --- In LTspice@, "xerties" <xerties@> wrote: I'm using one of LT's models for a buck/boost regulator, but the simulation runs incredibly slow. Cite. My CPU is certainly burning watts on it. io; Topics; Very slow simulation; × Close Search Search Cancel Date Date 1 - 9 of 9 previous page next page Very slow simulation xerties #34958 I'm using one of LT's models for a buck/boost regulator, but the simulation runs incredibly slow. To the best of my knowledge I have made the schematics and netlists the same in both of them and ran transient simulation for both of them. Then you can also use TINA from Texas Instrument which is free and allows as LTspice a bit of extra digital and ibis model. lib I don't want to bother posting up a . The only solution that worked was changing the gmin value to 10e-8 from 10e-12, but I am not sure what the real issue is or how this is going to affect the simulation results. However, once the simulation has completed, this format is non This simulation is very slow: it takes ~2 minutes for 20 ms. The circuit starts of the simulation pretty well, giving results that I would expect, but after about 4. tran settings and delete any maximum timestep. Diode 1N4148 aus obigem Beispiel). I think (but don't remember LTSpice version XVII(x64), Dec 5 2019. And r is an integer to use for oversampling of f. Specifically, the Q output of A3 (which is connected to the D input of A4) and the Q output of A7 are identical and perfectly aligned (i. Vlad _____ In case a simulation does not converge, LTspice provides options to change the settings. are as well. Separately, if you were able to use a V source, you can't enter its value as simply {a}*{b}; LTspice doesn't know what to do with a * in a V source if it's outside of curly braces. Subject: [LTspice] Re: Slow Simulation--- In LTspice@, "George Stamoulis" <stamo@> wrote: > > Hello there > I have a simulation that after some time runs extremelly > slowlly. The last entry in the K statement is the coupling coefficient, which can vary between 0 and 1, where 1 represents no leakage inductance. This power comes with a drawback: overuse or misuse of B sources can make the simulation run slow or fail to converge. I have to wait for like 30 seconds for it to finish. Ideal LC circuit decays over time in LTspice. Schematic Capture Pcb Design 3D Viewer Gerber Viewer SPICE Anschließend Simulationsparameter eingeben, z. Tags: software. asc files. Draft2. However I'm finding that after a few hundred concurrent simulations, the server slows down significantly and simulation times increase to 120+ seconds. These will be very helpful for first time users. Curve trace of the model in LTspice looks OK. ltspice simulation very slow Ernd Ert It's about the fastest simulator around, if you have troubles it's most probably because of the way the schematic is implemented or, my guess, bad models. LTSpice issue in using third party model file, throws "Ignoring empty pin current" and simulation is very slow. 1 \$\begingroup\$ See what happens if you pick a leakier diode (like a schottky) and increase the size of the resistor. The KiCad 2025 Fund Drive is here! Donate now Your support is critical to the development of KiCad in 2025 $16 donated $128,000 TOTAL Blog; Discover. Very strange. As a remedy to this situation, I recommend you to have what the simulator gives to you and postprocess this data to any form you like with a program, I am not using Windows 11 --But LTspice XVII on my laptop is also rather slow when painting the full 2 seconds of the simulation in the plot window. Feb 15, 2012 #8 S. 02 second. It runs extremely slow in LT. Here the sources BR - voltage dependent resistors, BC - voltage dependent capacitors. \$\endgroup\$ – You need to apply power to these op-amps; a simulator doesn't recognize a dual op-amp: - You apply power just as you have done for the un-circled op-amps except, you need to make the power supply polarity match the symbols on ALL the op-amp: -. I tried adding another pin to the definition, and this resolves the initial I built a closed-loop BUCK circuit. How to improve the simulation speed? 4338. So, preferably a simply solution based on ideal transistors that are easy to simulate for LTspice would be perfect. asc file). But when working from home over VPN, they slow down, a LOT. It is the aNPC circuit (only one leg) with the 6 gate drivers using GaN transistors. uic forces a different starting solution Yes, this is possible in LTspice. " If I remove one of the SW models, the sim runs OK. I've uploaded to the temp directory as supcapregd. Another possibility is that your I'm doing a project in a working for my a subject in my university. ; Simulation of this scheme is extremely slow (about 30us/sec). We also \$\begingroup\$ I didn't open the project yet but normally the simulation is slow when the simulation interval is too long (1 to 10 seconds). The calling sequence can be confusing when there are different process splits and options. JJ_023. Direct Newton iteration failed to find . Also, the voltages at It's a bit slower than filling out one and copying, but in the future having your circuit placed before you edit components will help ensure you don't forget things. The machine is based on an FX8350 with ram and given the significant I've done the noise analysis in LTSpice for the 5MHz frequency range I could potentially be looking at: I furthermore simulated the THD for a 200Hz signal: All of these simulations seem feasible, and I feel like I have all the information needed, yet I cannot find out how to calculate the ENOB of my system. Check the FAQ in the group's files for tips about problematic simulations. Hi, I am attaching my circuit here. Note that when you hover your mouse over the "OUT" net that connects to Rload1, and look in the lower left corner of the screen, LTspice tells you the actual net name is "DC_DC_IN" and not "OUT". I'm NOT using a TRIAC. When I simulate it in Falstad circuit simulator I get a result I expect, that is that voltage is regulated proportionally to the PWM of the generator. Try . Remove the resistors between the cathodes of the BST Schottky \$\begingroup\$ LTspice will use all the available cores (if allowed in the control panel), but only as many at a time as it deems so (internally decided), since the overhead of parallel computation can actually slow down a simulation. Your modulation is AC-coupled to the carrier In general, SPICE uses an adaptive step-size in transient simulations to minimize simulation time while maintaining accuracy. Follow edited Sep 22, 2021 at 9:22. LTSPice will implement some variation on this. This is why it is taking very long. com/roelvandepaarWith thanks & prai Our circuit is looking good, but to run a simulation, we need to add power supplies and let LTspice know what type of simulation we want to perform. LTspice® is a high performance SPICE simulation software, schematic capture and waveform viewer with enhancements and models for easing the simulation of analog circuits. LTSpice is only using approx 15-20% of my CPU and only ~6GB of RAM. Tstop is the duration of the simulation. I'd assume that it is difficult to compute To: LTspice@yahoogroups. asked Jun 27, 2019 at 21:09. Also, simply running wires between pins made me mad. When only placing this component, the simulation stuck at speed of picoseconds/second. It is found that the speed of simulation is very slow, and the transient simulation of 10ms takes half an hour. Voraussetzungen Unterschiede der Schularten Fernstudium. The device in this quarter to an AD8099. With the ferrite bead (EMI filter) VEMI rail measurement, the DC2822A demo board easily passes the conducted emissions limit line of 60 dBµV. Joined Mar 16, 2023 6. --*Plain Text* email -- it's an accessibility issue no proprietary attachments; no html mail Ich habe nun mal den LT317A (der internen Spice-Bibliothek) in meine Simulation eingebaut und siehe da, auch hier funktioniert die Simulation jetzt einwandfrei (in "Null-Komma-Nichts" an Sekunden sind die Kurven der Spannungen auf dem Schirm). TPS62A01 Buck converter. You can only re-start from the beginning. Normally, the appropriate method will be skipped automatically if it stucks. Here, we'll discuss three different simulation models, starting with the lowest complexity (linear), discussing a middle ground KiCad integrates the open source spice simulator ngspice to provide simulation capability in graphical form through integration with the Schematic Editor. then no; your simulation is over, LTspice closed it out. noise) DC Transfer Function LTspice is a high-performance Spice III simulator, schematic capture and waveform viewer with enhancements and models for easing the simulation of switching regulators. f is the sinusoidal frequency. How to prevent "Def Con" and simulation running at femtoseconds / second (running forever) for 1,600-run simulation . If these are the probes you refer to. zip. Nonlinear equation solvers in SPICE simulators. Is there any way to speed up the simulation without affecting the results, by changing the intervals I've been working with LTspice, and found that many times the simulation get very slow, in fact - not useable. Contact MOSIS at www. They may also have a I'm new to ltspice so I thought I'd run a simple simulation up through the rectifier and filters. 01 (instead of 0. It will not give you anything to plot, but it will indicate the voltages at all nodes and currents through all devices in the circuit. I don't know how many cores they have, but even my old one is 1 1/2year old only. Cadence Spectre, for instance, is way faster, but it's very expensive. 39 us doesn't seem that small to me, not when it's compared to your 10 ms simulation interval or 1 If you have the feeing your simulation runs too slow, help LTspice by changing some SPICE settings (. Copied the URL ! In this article, we will explain in detail how to set the simulation command used for the following six types of analysis. I picked up the models from the LTspice Files section: MOC308x. This circuit works well with Simetrix. How can I speed it up. × . Mar 11, 2024 Hallo meine ltspice spannungsvervielfacher Simulation ist sehr langsam ( es hat 4 tage gedauert um 15 s zu Simulieren), wie kann ich schneller Techniker. EMC_Filter_LTspice_Simulation_File. Is there a way to set the resulution down for the first 3800u to get a faster simulation? Or perhaps It's just the way LTSpice works. Num. Thread starter Charly Huang; Start date Mar 11, 2024; Search Forums; New Posts; C. What type of source should I place at ??? to mimic the antenna? Should I use a 1GHz sinusoidal voltage signal source or a current signal source at 1GHz for instance? And Hi everyone, I have a problem with transient simulation on LTSpice. This is a means of managing the size of waveform files by allowing startup Historically "numdgt" was used to set the number of significant figures used for output data. 001), but with no major success. So all I want is to supply a 120VAC supply (about 170Vpeak) at 60Hz and to keep the MOC3083's LED at full intensity EMC_Filter_LTspice_Simulation_File. This is confirmed as when the TPS61170 is removed from the circuit, the simulation runs as expected. Also, I have found another problem. 4. Any help or direction will be appreciated. SherpaDoug Full Member level 2. Unfortunately, LTSpice doesn't seem to be capable of simulating a sine wave. Just to fix ideas take the Colpitts oscillator and perform a transient analysis (including the default DC initial transient solution). Whether or not MOSIS will give you the models depends on what kind of organization you represent (educational institutions get special consideration) and whether you want models for the newest processes or for older processes. Does the team have any recommendations here to attempt to speed up the runtime? It would \$\begingroup\$ LTspice will use all the available cores (if allowed in the control panel), but only as many at a time as it deems so (internally decided), since the overhead of parallel computation can actually slow down a simulation. , without any delay between one and the other). I have uploaded a PDF of the steps to be followed for each simulation, and the final simulation file. NPN_Colpitts_oscillator_base_coil. But the nested/hierarchical nature of the library calls are a fundamental feature. Transient ðlThe transient analysis is probably the most important analysis you can run in LTSpice, and it computes various values I am starting with some linear simulations to ensure everything is working, but the simualtor gets stuck on the "initializing circuit matrix" step. asc. Can anyone help with that? I've tried several solutions (see below) There are a few ways to improve the speed of your LTSpice simulation. The simulator is running correctly and I believe this data is valid. In LTspice, perhaps an adaptation of something like this: Above, v is the output voltage you want. Simulation von 0 bis 10 ms: Ergebnis für Spannung V2: 2. Image 1: Image 2: Image 3: Image 4: mosfet; ltspice; mosfet-driver; Share. The first method is direct Newton-Raphson iteration. When I run your schematic with the modified Trap method I see the same 500 nS/S simulation rate, But when I set to Gear method the simulation rate increased to around 80u/S. png. Remove the gate resistors - this is just bad design practice and will also slow down your simulation time. asc file. This simulation does not include the battery model, as the LT3474 does, because it ran slowly anyways. asc Part Number: LMZ14202EXT Other Parts Discussed in Thread: TINA-TI, LMZ14202 Tool/software: TINA-TI or Spice Models Hello there, I'm having a tough time simulating this model on LTSPICE because it just takes too long (up to 30 min), since I need to make some Monte-Carlo simulations it'll take forever! My LTSpice simulation (fresh download from yesterday) always stops (gets super slow) after approx. I have searched the forum for tips, but I still have problems understanding what to do to increase the simulation speed. In this video, I show how to speed up your simulation by setting initial conditions. Folks, Yahoo has made the sign-in procedure so onerous (can't get in anymore) that I'll ask here instead of the LTSpice group: I want to do some noise simulations, for example with a TI opamp in there. With LTspice, I am getting a frequency of around 26GHz, whereas with ngspice I am getting around 20GHz (a period of around 50ps). Files > Lib > OPA2376_test. 2. options srcsteps=0". The machine is based on an FX8350 with ram and given the significant I have a very simple simulation. It ends up running extremely slow and I never seem to be able to finish the simulation, since the speed Looking for some advice on creating a constant (linear) ramp which meets a certain specification, I've designed this example which works well in ideal simulation but I cannot get it to work in SPICE. As shown in Figure 1, you can open the “Control Panel” and then change the settings defined in the “SPICE” tab. All the usual tweaks one does to optimize a machine. This is going extremely slow, though. This can be done Subject: [LTspice] Re: Transient simulation slow to complete *** WARNING *** This message has originated outside your organisation, either from an external partner or the Global Internet. Frequent Contributor; Posts: 370; Country: Help Choosing a Simulator - LTspice, QSPICE or TINA-TI Whenever you relax these tolerances, you risk having bad data from your simulation. Joined Jun 21, 2011 Messages 149 Helped 28 Reputation 56 Reaction score 28 Trophy points 1,308 Location Cape Cod, USA Visit site Activity points 2,260 There is a "stop the simulation if a steady state The question is very simple, why we have a DC offset when using capacitors as DC block in LTspice (even with a parallel resistor)? The facts: With Stop time = 10 m (very large!), Maximum Timestep = 0. 01 n (very small!): SPICE log (no floating nodes): Simulation command: Is there anything I should fix? Thanks a lot! I have tried importing the PSpice model of TPS57160-Q1 into LTspice, since I had some problems simulating the device in Webench(see other posts). I'm making my first attempt at simulating a very simple zero-cross circuit using the TYN640 SCR and the MOC3083 (5mA) zero-cross opto-triac as a trigger. I agree that the simulation run time is quite long. unknown spice device type [LT spice] Hot Network Questions Would having a review article published in a reputable journal as sole author look good to grad programs? How is the I've recently been using LTSpice to simulate a control circuit for a nonlinear system where the control principles have been verified on MATLAB. Theoretically I would expect in out an impulse of 20 usec, instead at the arrival Compared to other simulation tools, PSpice takes more time to finish simulations. where "1" is typ, "2" is fast, and "3" is slow. Edit Simulation Command. (Use Electronics: How to trace down why LTSpice simulation is slow?Helpful? Please support me on Patreon: https://www. zip This simulation was a little bit faster with the options Hello, I have a problem with the simulation with LTSpice, I created the device from the . I was running the simulation attached. 01 second, and again from 1. But different transformers will behave very differently. tran) is also a little odd. Thread Starter. I often then re-run the simulation with changed component values, so these voltage/current probes are assumed by LT spice. DC2822A V IN configuration, comparison of LTspice and actual EMC lab emissions. \$\begingroup\$ @SubhransuSekharBhattacharya Meh, LtSpice has a GUI however rough, I learned spice typing in the netlists manually on a VT220 terminal (No graphics) and running the model as a batch job, then plotting the curves by hand on graph paper from the printout. tran 0 4000u 3900u" With a calculating time not more than 10us/s it needs really long to simulate. 6ms simulation duration). Here is a link to the files for both LTspice and Xschem+Ngspice. user211748 user211748 \$\endgroup\$ 4. The circuit itself is I have a brand new 6th generation i7 laptop with 16G RAM. A 500ms simulation with this much oscillation will be slow with any simulator. Just a voltage source set to an 80v DC offset with an amplitude of 2 volts and frequency of 1500Hz. lianghonghao. Am I (see screenshot)? Would someone mind pointing LTspice Basics. In LTspice, if "numdgt" is set to be > 6, double precision is used for dependent variable data. Setting initial conditions for certain voltage has been tried in the uploaded . param Pch DeviceName+10. Personally, I haven't found many cases where an 8/16 CPU feelt slow, and using a cluster for computing may imply having extremely complicated schematics Are you sure you wish to delete this message from the message archives of LTspice@groups. To add a voltage source, select and place (Draft > Component) a voltage/Voltage Source component in an empty area I'm running 64 concurrent simulations of LTSpice using Wine on a 64-core Centos linux machine to acquire ideally several million data points. Most probably, your simulation takes so much time due to convergence issues. Für How can I make the simulation faster? I use LTspice and I made similar simulation using LT3502 (it works at 2. Finanzierung Bildungskredit Aufstiegs-BAföG Bildungsprämie Begabtenförderung Weiterbildung von der Steuer absetzen Kreditkarten-Vergleich. Running total simulation of 5ms at this timestep will take very long. Although, this will produce more accurate results. Both are just as slow. These sorts of things have always been very fast with ngspice, so I figure I must just be using ltspice incorrectly. B. 7 Nevertheless, the free version allows a limited number of component, and quite slow in everyday use. sim_batch. I was wondering if the models could be simplified a bit for better performance. Here is the log file: Model "elen254p": Oxide thickness thinner than recommended for a level 3 MOSFET. Helmut Sennewald The following model causes my transient simulation to slow to 10's of ps per second in LTspice when the circuit should respond in milliseconds. So slow signals (modulation) spend long 'boring' intervals generating 100 MHz cycles. SPICE, and LTspice, adjust the time step size dynamically. the simulation is extremely slow. This can be done LTSpice has the element called Lossy transmission line (symbol name ltline):. net. pivrel. Most of that time is while it is drawing the sinewaves from 0 to 0. RG58 / 50 ) 90 13. This has nothing to do with the speed of the simulation. Related Content Designing Modern Industrial Drives with Silicon Carbide; Practical FIR Filter Design: Part 1 - Design with Octave or Matlab ; LTSpice Simulation Using Nevertheless I got it working, but with a slower simulation speed. I thought it was reasonable to test such a circuit. txt If all that fails, you can try with the Author Topic: Help Choosing a Simulator - LTspice, QSPICE or TINA-TI (Read 77653 times) 0 Members and 4 Guests are viewing this topic. LTspice LTspice Simulation 2019-05-07 2022-12-11. Files > Temp > OPA2376_slow1. Cedric Cedric. 5uS. 4 Einbau zusätzlicher Modelle und Teilschaltungen LTspice enthält bereits mehrere Bibliotheken, in denen Modellparameter für eine Reihe von Standard-Bauelementen abgelegt sind (z. As for the voltage sources, for this circuit you'll want to Remove the series resistance in both of the power supplies. If you used Simulate > Pause (or ctrl-P), then you can resume it MOC3083 + TYN640 simulation running slow Jon Kirwan #67973 . 1. Try including SPICE directive . It is (I think!!!) in a menu selection marked "controls". I think the software is so slow or so complex LTSpice Basic Tutorial Page8 IV. But I wanted to connect the converter with a battery model and test it to depletion. You can see I put ??? question mark there in above schematics. If that fails, LTSpice will try the following strategies in order by default: Adaptive gmin stepping; Adaptive source stepping "Pseudo Transient" How to speed up the simulation with LTspice, I try with simple DC/DC converter but it takes really long ? 37dcto3v3. Our enhancements to Spice have made simulating switching regulators extremely fast compared to normal Spice simulators, allowing the user to view waveforms for most switching Yes -- but only if you had Paused the simulation. 437 4 4 silver badges 11 LTspice includes simulation commands for transient, linearized small signal ac, dc sweep, noise, dc operating point, and small signal dc transfer function analysis. But Second, try changing the solver. It's shipped as a bouquet of different modules. When simulation is run pressing ESC skips the pseudo analysis and a After a slow run it may run slowly or normally the next attempt. Simulation of Cable Loss at 100MHz 91 13. asy st_scr. You should not expect that. In this article, we'll learn how we can model inductors using LTspice, a circuit simulation program where the accuracy of the simulations depends on the accuracy of the models used. Loading and saving file times are about the same, so why should the simulation be drastically Simulation of the Example with LTspice 85 13. First, thanks for making the asc file, I still haven't working that side of ltspice out. Basically the program is extremely slow and by slow I mean it takes several hours to complete the calculation. lzxs qurgbcmi tmziq vrtag jrvru pib cjcpr hdwviy fwjratc breqr
