Hello all, Please have a look at the plot_stepped_meas_data_test.asc file which I have uploaded in the Temp folder. It is a tran simulation, with two parameter sweeps. Once the simulation is done, I open the log file and I choose the option "Plot step'ed .meas data". This brings up a new plot window with the vcc_hv parameter used on the horizontal axis. How can I change the horizontal axis to use the Inductance parameter instead? If I write-click on the horizontal axis and change the Quantity plotted field from Vcc_hv to Inductance I get an error: "undefined symbol in "Inductance"" The only way I have found to do it is by changing the order of the .step param directives in the spice netlist file, prior to running the simulation. But after running the simulation, it seems the horizontal axis is stuck at the parameter used in the first .step param directive used in the netlist file, without any possibility of switching the parameter used for the horizontal axis of the plotted data. Is there any way of changing the horizontal axis of the plotted data after the simulation has run? Best regards, Cristian

I need the LTSpice model of SN74HCS125/126. The PSpice model is not compatible with LTSpice. And the .lib file mentioned in the TI's forum is not useful. https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/151/SN74HCS125.lib

Hello,As shown in the photos , my CSV file has a pulse shape according to excel. But when i put it into PWL source in LTspise i get only noise. LTspice files are attached. where did i go wrong? https://groups.io/g/LTspice/photo/294510/3838345?p=Created%2C%2C%2C20%2C2%2C0%2C0 https://groups.io/g/LTspice/photo/294510/3838344?p=Created%2C%2C%2C20%2C2%2C0%2C0 https://groups.io/g/LTspice/files/Temp/john23/tst2.zip

Here is my sim file and Tony's MOSFET model that I am trying to use to see the flyback pulses. So far they are not showing in the outputs but then, as a relative newbie to Spice, there is probably something very simple I have not done right. Thanks Julian https://groups.io/g/LTspice/files/Temp/Capacitor%20Pulse%20Charging

Hi everyone. LTSpice XVII. I need a simple RC 2nd order Butterworth high pass filter, Fc=159Hz (Q=0.707) to use in single driver audio box to flatten the cone excursion under the maximun value of the driver (I use the dedicated "Filters" option of WinISD, showing that the filter above is the suitable one). In LTSpice XVII, I set up a RC filter diagram having the voltage surce set at 1V and a sweep from 10 to 20kHz, but simulating it, the Fc at -3dB was not 159Hz, rather about 426Hz, but at the cut off frequency of 159Hz, the gain is -9.55dB. The two resitors value is 10k and the two capacitors value is 100nF, as per the textbook calculation for this filter type. I can't figure out what's going wrong. Please help! Here's the relevant circuit text: ---------------------------------------------- Version 4 SHEET 1 880 680 WIRE -80 -48 -208 -48 WIRE 64 -48 -16 -48 WIRE 144 -48 64 -48 WIRE 320 -48 320 -96 WIRE 320 -48 208 -48 WIRE -208 0 -208 -48 WIRE 64 16 64 -48 WIRE 320 16 320 -48 WIRE -208 144 -208 80 WIRE 64 144 64 96 WIRE 64 144 -208 144 WIRE 320 144 320 96 WIRE 320 144 64 144 WIRE 64 192 64 144 FLAG 64 192 0 FLAG 320 -96 Out SYMBOL res 80 112 R180 WINDOW 0 36 76 Left 2 WINDOW 3 36 40 Left 2 SYMATTR InstName R1 SYMATTR Value 10k SYMBOL res 336 112 R180 WINDOW 0 36 76 Left 2 WINDOW 3 36 40 Left 2 SYMATTR InstName R2 SYMATTR Value 10k SYMBOL cap -16 -32 M270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName C1 SYMATTR Value 0.1µ SYMATTR SpiceLine V=100 Irms=0 Rser=0.0371 Lser=1.1p mfg="Würth Elektronik" pn="885382208006 WCAP-CSST 1206" type="X7R" SYMBOL voltage -208 -16 R0 WINDOW 3 24 152 Left 2 WINDOW 123 24 124 Left 2 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value SINE(0 1) SYMATTR Value2 AC 1 SYMBOL cap 208 -32 M270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName C2 SYMATTR Value 0.1µ SYMATTR SpiceLine V=100 Irms=0 Rser=0.0371 Lser=1.1p mfg="Würth Elektronik" pn="885382208006 WCAP-CSST 1206" type="X7R" TEXT -242 200 Left 2 !.ac dec 100 10 20k TEXT -192 248 Left 2 ;Filtro RC del 2° ordine, Fc = 50Hz, Q = 0.2 ----------------------------------------------

Hello , I have built an analog sequencer as shown below. On of the Biased is the Vdd,when i look at the EVAL board schematics I see inductor capacitor structure. The Eval board is built for manual switching. I know these inductors are a power delivery /RF choke system. RFchoke is not allowing the RF signal to travel threw the DC port ( only rf output port). given my VDD biasing circuit how can I know the on one hand the DC pulse will come to the Output non destorted but on the other hand the RF signal will be blocked from traveling the wrong path ? Is there any LTspice method or real life Lab method to test that? Thanks. LTSpice files are attached https://www.minicircuits.com/pdfs/PMA5-83-2W+.pdf https://groups.io/g/LTspice/photo/294510/3836362?p=Created%2C%2C%2C20%2C2%2C0%2C0 https://groups.io/g/LTspice/files/Temp/john23/lt2_circuit.zip

Hi all- I'm back again trying to recreate a circuit that someone else built in LTSpice. This time I'm having trouble running the below simulation: https://groups.io/g/LTspice/files/Temp/LM4050_stripped.asc I was not given any additional files beyond the .asc; I do not have a model for the LM4050 and I am not sure how the original designer obtained the model. Or, if they tweaked an existing model and renamed it to LM4050?? I really don't understand what it is they did here and am hoping someone can help me decipher. Thanks! -May

Hello,regarding the spice models of the capacitors and inductors. I know that i should not choose random manufacturer models in LTspice. Instead i should extract ESR ESL Q from datasheet. For example: 4.7uF 12063C475KAT2A AVX CORPORATION https://www.mouser.com/datasheet/2/40/KGM_X7R-3223212.pdf I only see impedance as a function of frequency. how do i extract series inductance , series resistance, paralel capacitance,paralel resistance from the data sheet? Thanks.

Hi, I have uploaded a file with schematics which created the pics I uploaded of the problem I had. Only recently noticed by the way. The main issue is seeing the ohms symbol (Ω) in the status bar at the bottom left instead of a square. The waveform windows display it perfectly - y-axis on the left and on the right as well. Not the x-axis though, only values there (the current, voltage and temperature (℃) display perfectly). The schematic shows square for Unicode 0x03A9 as well. Unicode 0x2126 displays. The ohms symbol displays everywhere else: picking a resistance/resistor, picking a value for an inductor, voltage source and so on - the pics confirm this. At first I thought some font or fonts were not installed in Wine. But seeing the symbol display everywhere but the status bar I thought maybe something else - unless the status bar uses another font or derivative. Over the weekend I scratched through quite a few messages regarding Wine / Unicode problems on here. The general consensus (Wine users) was that the symbol was not really used on the schematic, so, not a big deal. Tony also thought missing font maybe which made me think to look around for missing fonts on the net. My search first led me to installing "winetricks" and the "corefonts". This did not fix my problem - it fixed a few problems for other people using Windows apps, so it can also be a solution to look at for some problems. My search then led me to WineHQ's bug section. Here I discovered a few video games crashed with claiming Arial and/or Tahoma fonts were not installed. The suggestions were installing the corefonts, arial32.exe and tahoma32.exe Found arial32.exe and tahoma32.exe here: http://dir.vietnam.online.fr/home/vnDownloads.htm (not a secure site). Checked the files online but they were clean. I installed them using: WINEPREFIX=~/.wLTspice24/ wine arial32.exe WINEPREFIX=~/.wLTspice24/ wine tahoma32.exe Of course ".wLTspice24" is my wine bottle, yours will be different. Bob's your uncle, as they say. Pic-27 shows the result. The schematics are slightly different - the text portions, maybe the characters of the font changed a little in shape, boldness. The status bar is very much bolder but Ω shows up now. "Oh, well", as Peter Green said. -- -- Regards, Abes

I tried modelling this very simple coil driver suggested by the manufacturer of a purchased instrument. The results are very confusing, so I suspected I did something stupid creating the model, but so far, I can't see what's wrong. It is supposed to convert a DAC programmable bipolar input voltage to corresponding current in the grounded coil. Coil is specified as 32 ohms, 2mH, and resonance >10kHz. The current output should also be bipolar… When I run it, the buffer’s output sits at +10VDC plus/minus mVs, with the coil current around 320mA, plus/minus uAs, rather than zero, plus/minus up to 150mA. Please take a look at the original (in the Zip for convenience, but also uploaded to Photos), and see what might be wrong. I am not by any means certain the suggested circuit is correct, BTW! Thanks, Dave

I am new in LTspice and optimization. Could someone please get me started on how to use LTspice and MATLAB together to run a gradient descent optimization and update the value of parameters? I am trying to simulate a Nonlinear Transmission Line and optimize the output. Any help would be appreciated.

Assuming for now that none of the Library devices are anywhere near similar to some IR and R/G/B/Y diodes I’m looking at, and I cannot locate SPICE models for them… What’s the best way to tweak a model (from the Library), for Vfwd at Ifwd, and preferably, over some temperature range? Dave

Hi everyone, Here are my sim files and an image of the sim file marked up with lab measurements: https://groups.io/g/LTspice/files/Temp/Watchdog_test.zip So, I am getting caught up on a new-to-me board and I'm getting stuck on a few things. In simulation, regardless of whether the input to the IL611 (modeled as a Schmitt trigger) is net 3.3V or net 0V, the MR_ signal is 5V. This is not what I would have expected. I would have expected MR_ to change based on the input from the IL611. In lab, when the net voltage from LVDS_P_2 to LVDS_N_2 is 3.3V, the output of the IL611 is definitely 0V, which gives an MR_ of 5V and a MAX16058 (not shown in sim) output of 1.8V. However, when the net voltage from LVDS_P_2 to LVDS_N_2 is 0V, the output of the IL611 floats up to 0.7V, which in turn causes MR_ to float between 1.2V and 5V, which then causes the MAX16058 output to be 0V. The one thing I think I noticed was that the Spice .lib file and the SSM3K329R appear to have different pinouts?? I am fundamentally unsure if I am using the Spice model correctly...or if there is something fundamentally wrong with this circuit that I inherited. Either way, I could use some help debugging the Spice model to see if there is something I'm doing wrong. Thanks! -MAY

Dear all, I want to simulate sleep mode in dcdc regulator. Any schematics already simulated in the forum or any material is available? With regards,

Hello dear people, I haven't been here for a long time. It's great that you exist and I wish you all good health, happiness and success with LTspice. I wanted to display the characteristics of tubes as they are shown in the data sheets. The idea is this: I want to compare the tube models exactly with the data sheets. Would someone please show me which commands I can use to do this and which options are good for the display? You are welcome to write to me directly at sprussog@... Best wishes to you all from Steffen

I want to ask from where can i get 90nm, 65nm or 45nm (IBM,TSMC) spice model file that I can run at LTspice ?

Just a heads-up for Wine users on distros that run a bit behind Arch: avoid upgrading to Wine 9.17. This release has a regression that lost support for drag'n'drop, which affects LTspice and other applications. Stay on 9.16 (or revert if already on 9.17) until 9.18 comes your way, which fixes the issue. -- Regards, Tony

Has anyone successfully installed LTspice 24 windows version on macOS with Wine or another tool? Preferably something open source or free to use vs paying for crossover. If so can you help share what you did?

Does anyone know where I can get a Spice model for the stw12n170k5 power N-Channel MOSFET? STM have so far not responded. Thank you

fan_slow.zip is the newest version my schematic and files for simulating a hi-side gate driver with logic-level inputs and a modest-power IGBT driving a mixed resistive and capacitive load as the target. I was happy to see the advice that OnSemi has a part (FAN73711) very similar to the older Fairchild FAN7371 I had soldered into my experiments. It comes with an LTspice-specific encrypted model, much better fit than the ancient Pspice model I was trying to adapt. And it runs!! Horraay! The output even resembles what I had expected. But instead of a few seconds to model a few cycles it has so far run more than 36 hours to do only 3/4 of that span. And there are messages about “def con 1” making me think the model program is unhappy with something I asked for. The model for the IGBT has some notes in it about settings for the transient analysis — I did not understand them but I mention them because they may be a key to the glacial performance. I would have just split the schematic into a test of the IGBT model with ideal voltage pulses driving it to determine which newly functional model was most broken, but I also am unclear on how to get a Mac to run multiple copies of LTspice at once? There seems to be a single-threaded copy running that wants to do any new schematics in the same thread as the compute-bound one I’m already running. Anyway, this group has already given me enough clues to get a running model — it seems greedy to want it to run faster — but the speed really is too slow for most purposes. Anybody see what’s wrong? I did not include the plot file — I assume that starting the rain locally and seeing the beginning of it is the protocol? Thanks for your help! —Paul