hybridfree/eevblog-posts huggingface dataset:
LTspice - new symbol, no <InstName> functionality - Page 1
Forum section: electronics / projects

author: Greybeard
author_rank: Frequent Contributor
timestamp: August 07, 2025, 03:21:12 pm
content: Hi,I searched unsuccessfully for a Hammond 125B audio transformer model, but only found one for the similar Hammond 125A as a zip file (.asy+.asc).Since I don't like the symbol, I drew a new one from scratch.Problem:The<InstName>line is missing in my new model.When I insert theold symbolinto a new schematic, LTspice generatesX1, X2, X3... as the component names. So far, so good.When I insert thenew symbolinto a new schematic, LTspicedoesn't generate a component name.I tried inserting<InstName>as text into my new symbol, but when I insert the component into the schematic, the components' name is "<InstName>" (or whatever I previously inserted into the symbol).When I insert the component repeatedly, the number doesn't increment.Can someone please explain how to add a working <InstName> functionality?

author: Ian.M
author_rank: Super Contributor
timestamp: August 07, 2025, 06:00:16 pm
content: Open the Attributes window (Menu: Edit: Attributes: Attributes Window, or Ctrl-W) and add it from there. You'll probably also need to edit the attributes (Menu: Edit: Attributes: Edit Attributes, or Ctrl-A) to match those in the original symbol.

author: Greybeard
author_rank: Frequent Contributor
timestamp: August 07, 2025, 07:27:25 pm
content: Both attribute windows look pretty the same (left vs. right):

author: Ian.M
author_rank: Super Contributor
timestamp: August 07, 2025, 08:24:23 pm
content: Good. Now, open the attribute window, (not the editor), click InstName, then  and place it.

author: Greybeard
author_rank: Frequent Contributor
timestamp: August 07, 2025, 08:35:31 pm
content: Thank you, Ian.It works perfectly now!

author: Greybeard
author_rank: Frequent Contributor
timestamp: August 07, 2025, 10:32:38 pm
content: Maybe my template still has an error: the phase may be reversed.How to correctly read transformer symbol from the official data sheet without any polarity dots?How can I correct the phase in the symbol without simply moving the polarity indicator dots.I've already tried correcting the assignment of the pin names to the netlist numbers (1->2 and 2->1), but it didn't change anything...

author: Ian.M
author_rank: Super Contributor
timestamp: August 07, 2025, 11:20:56 pm
content: Hierarchical schematics 'Block' symbols don't use the netlist order. Instead they match pin names to node names in the block's .asc file (which must have the same root name as the symbol .asy file). You'll need to edit the block .asy file and swap node names there.

author: Greybeard
author_rank: Frequent Contributor
timestamp: August 07, 2025, 11:24:35 pm
content: I swapped BN and BU in the subcircuit's .asc file.It's working correctly now:
LTSpice Power Estimation of LTC6363 FDA - Page 1
Forum section: electronics / projects

author: davegravy
author_rank: Regular Contributor
timestamp: February 25, 2022, 09:43:33 pm
content: I'm trying to model power dissipation for this IC and getting questionable results. I tried to reproduce the scenario given in theLTC6363 datasheet (page 29)for worst-case power dissipation.The datasheet predicts 97mW total dissipation. The simulation matches the power dissipation through the load, feedback, and input resistors (12.5mW each resistor) but the term for quiescent current is way off. The datasheet predicts 22mW but LTSpice predicts 66mW.Is LT's SPICE model wrong or am I using/interpreting the software incorrectly?My LTSpice circuit is attached.

author: davegravy
author_rank: Regular Contributor
timestamp: February 25, 2022, 09:54:20 pm
content: Interestingly if I ground both inputs to eliminate the resistor dissipation terms, the predicted dissipation is ~20mW which lines up pretty close with the first term of the datasheet. Not sure then why the +/- 2.5V input case is so far off.
LTSPICE question - Page 1
Forum section: electronics / projects

author: Wimberleytech
author_rank: Super Contributor
timestamp: November 30, 2018, 06:55:25 pm
content: I have created a custom model for a shunt regulator. I opened the netlist in LTSPICE, then created a symbol, placed it in the schematic...all is well.Is there a way to navigate to the netlist directly from the LTSPICE GUI? I can click on the symbol and navigate to the symbol editor, but I do not see a way to get to the netlist.I can only do this by generating a top-level netlist and from there see where it is located (assuming I did not know already!) and click on it from the Windows Explorer.

author: Wimberleytech
author_rank: Super Contributor
timestamp: December 01, 2018, 01:27:30 am
content: I guess the answer is "no."

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 01, 2018, 06:38:58 am
content: Second result on Google?http://ltwiki.org/LTspiceHelp/LTspiceHelp/Spice_Netlist.htmTim

author: Wimberleytech
author_rank: Super Contributor
timestamp: December 01, 2018, 12:28:29 pm
content: Quote from: T3sl4co1l on December 01, 2018, 06:38:58 amThanks for the snark. Perhaps my question was not clear.Suppose you have a schematic in LTSPICE.You are going to add a new custom device.This is simple to do:https://www.analog.com/en/technical-articles/ltspice-simple-steps-to-import-third-party-models.htmlPlace the device in your schematic and go on your merry way.Later you want to edit the netlist of the custom device. This is easy to do outside of the GUI.However, I would like to push into the netlist while inside the GUI.I do not see a way to do that.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 01, 2018, 04:06:56 pm
content: Oh, the component model, not the full thing!I'd just as well put the .SUBCKT on the schematic as a comment^Hcode box.Tim

author: Wimberleytech
author_rank: Super Contributor
timestamp: December 01, 2018, 04:48:29 pm
content: Quote from: T3sl4co1l on December 01, 2018, 04:06:56 pmYup.I could do it that way I suppose, it would be nice to be able to traverse the hierarchy ultimately bringing up a text netlist when you reach the netlist level.It is not often that I will do this, so I will live with viewing outside of the GUI.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 02, 2018, 07:43:53 am
content: Could do hierarchical design but I think that's schematic not netlist view? So, anything you have in netlist form would have to be rendered in schematic form.Tim

author: Ian.M
author_rank: Super Contributor
timestamp: December 02, 2018, 09:10:45 am
content: You can right click a .lib command and then open the file it refers to, so the best option may be to add.lib your_subcircuit.cirto the schematic, which should open it if its in any folder that LTSPICE searches for models.
LTSPICE question - Page 1
Forum section: electronics / projects

author: materials_guy
author_rank: Contributor
timestamp: January 13, 2016, 01:35:41 am
content: In LTSPICE, is there a way to model a resistor that has a frequency dependent, pure resistance (not a reactance).For example the mystery component would have 0 Ohms at 100Hz and rise to 1.0 Ohm at 400Hz whilst the reactive component is +/-j0 Ohms over this range.Thanks in advance!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 13, 2016, 06:17:18 am
content: Yes, but it's only suitable for AC steady state analysis. A transient simulation is, in principle, possible, but the method Spice uses to resolve a frequency model is inefficient to say the least. This reflects the nonphysical and/or noncausal nature of your model.Do you have a specific application?Tim

author: materials_guy
author_rank: Contributor
timestamp: January 13, 2016, 10:50:24 am
content: The analysis is steady state AC. The application is modeling radiation impedance of a horn throat. The Re part is frequency dependent and at low frequencies =0.

author: Kevin.D
author_rank: Frequent Contributor
timestamp: January 13, 2016, 02:13:58 pm
content: Arbitrary Resistors ? . (I often get convergence errors though when I have used them)http://ltwiki.org/index.php5?title=B_sources_(complete_reference)

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 15, 2016, 07:27:18 am
content: Ah, well then it should be sufficient to use an RL equivalent which has the desired behavior, because I'm guessing the imaginary impedance will be positive and also proportional to frequency (for f << fo)!Tim

author: Kalvin
author_rank: Super Contributor
timestamp: January 15, 2016, 08:07:53 am
content: See "Using Coilcraft's Advanced Models in LTSpice" how to simulate frequency dependent resistors:http://www.coilcraft.com/modelsltpice.cfm- Use LTspice component g2 and LAPLACE=abs(1/s) or similar expressions.Here another useful article: "HOW TO SIMULATE A FREQUENCY DEPENDENT INDUCTOR"http://iiitdelectronics.blogspot.fi/2013/04/how-to-simulate-frequency-dependent.htmlHere are some undocumented LTspice resistor tricks:http://ltwiki.org/index.php5?title=Undocumented_LTspice#Resistors

author: materials_guy
author_rank: Contributor
timestamp: January 18, 2016, 05:42:54 pm
content: The G2 element did the trick!Thank you!
ltspice ; run simulaton, without changing the waveform zoom level and focus - Page 1
Forum section: electronics / projects

author: julian1
author_rank: Frequent Contributor
timestamp: October 20, 2022, 05:00:18 am
content: I often zoom in on a point in time in the waveform viewer, and want to quickly tweak something, then rerun the simulation to observe the effect.But when the sim is restarted, the origin and scaling axis are always reset. So after each run it is necessary to re-navigate back to the area/point of interest. Is there a way to override this behavior, to force the zoom area/ viewport not to move?Note, that it's not a matter of just changing the initial starting conditions, because I am interested in the cumulative state of the circuit.

author: magic
author_rank: Super Contributor
timestamp: October 20, 2022, 05:32:31 am
content: Not sure if it can be done, but IIIRC the change to full waveform view after simulation appears in change history and you can undo it by pressing F9, which takes you back to the point you were viewing before rerunning the sim.editI just tried it on my (somewhat old) LTspice installation. What exactly happens, is that my current view is replaced with full waveform view, and I can go back to the previous view with F9Of course, some meaningless change can be made so that it will be the change that will get nuked and F9 will take you to where you want.Maybe there are better solutions but I always got by with that.

author: julian1
author_rank: Frequent Contributor
timestamp: October 20, 2022, 05:49:28 am
content: Quote from: magic on October 20, 2022, 05:32:31 amyeah, that's workable. Just make a single waveform edit - eg. click a random resistor for current, run sim, then hit f9 and it undo's the added resistor trace, while restoring the viewport.

author: RoGeorge
author_rank: Super Contributor
timestamp: October 20, 2022, 06:57:32 am
content: Adjust the waveform view as you wish, then save.Run again the simulation, then reload the saved .plt file.To make it easier, associate the "Space" key with reload plot settings fromTools -> Control panel -> Waveforms -> Hot Keys -> WaveForm -> Reload Plot Settings File: SpaceThen, once you saved the preferred view, run a new simulation, click on the plots window, then press the 'Space' key to reload previous view.

author: julian1
author_rank: Frequent Contributor
timestamp: October 20, 2022, 07:25:56 am
content: Thanks, that's perfect. I track plt files in source control, but never realized they store/contain the x,y viewport.The 'space' key was already default mapped to reload in the waveform hotkeys. Knowing that a reload action exists makes all the difference.

author: RoGeorge
author_rank: Super Contributor
timestamp: October 20, 2022, 07:48:13 am
content: By default it's loaded the .plt with the same name as the .asc file. If needed, more .plt files can be created with 'save as' (then load manually by opening the wished .plt file).Another trick (saving .plt not required), in a transient simulation set the "Time to start saving data:" to start at the moment you want to view the plots. The disadvantage is that anything before that time is not possible to plot.
LTspice schematics must go into another tool for generating board layout - Page 1
Forum section: electronics / projects

author: abdulbadii
author_rank: Frequent Contributor
timestamp: September 28, 2021, 11:20:04 pm
content: What would be convenient way importing LTspice schematics into some tools on Linux for generating board layout, in definitive clear step by steppcb and Kicad is readily installedPlease any experienced one share and show us

author: jmw
author_rank: Frequent Contributor
timestamp: September 28, 2021, 11:40:05 pm
content: Step by step: select parts that match your simulation's components and put them in to KiCad's schematic editor. LTspice deals with idealized passives and models; for prototyping you need to pick real components that are linked to a BOM and a footprint, which LTspice knows nothing about.Edit to add: if you want to try new and bleeding edge, there are tools likehttps://www.flux.aithat aim to integrate simulation, ECAD, MCAD, and firmware development. It's being developed by a friend of a friend of mine. Current tools don't lend themselves to turning a simulation into a schematic without basically redrawing it; some EDA packages have internal SPICE engines, but seemingly nobody uses them.

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 29, 2021, 05:55:51 pm
content: You can also try that, but haven't tested it:https://github.com/laurentc2/LTspice2KicadI personally do not really recommend using LTSpice as a schematics editor for anything else than simulation purposes, as it's pretty rough, but that's your call.

author: JPortici
author_rank: Super Contributor
timestamp: October 01, 2021, 04:52:38 am
content: Quote from: jmw on September 28, 2021, 11:40:05 pmWeb based <anything>. No thanks. I understand why but just no

author: tmadness
author_rank: Regular Contributor
timestamp: October 01, 2021, 06:31:29 am
content: Kicad has a built in simulator. Don't know much about it but it's been there for a while.Altium's simulator didn't look half bad.The flux ai is an intriguing project. But browser based ... yuk. Come on, something that is as performance intensive as a pcb editor needs to be native. Also this stuff is cloud dependent...
LTSpice - simulating the switching of an inductor - Page 1
Forum section: electronics / projects

author: atferrari
author_rank: Frequent Contributor
timestamp: January 18, 2015, 03:09:55 pm
content: Using LTSpice to simulate the switching of an inductor as per attached .asc file (please delete the.txtpart).I understand that the emitter current (Q2), at the moment it is turned on, should be positive starting from 0 mA.LTSpice insists in showing a negative current which contradicts the sense of the one through L2, which is positive, starting from 0.BTW, current through D2 is consistent with that of L2.At lost here...

author: bktemp
author_rank: Super Contributor
timestamp: January 18, 2015, 03:22:31 pm
content: LTSpice shows the current flowing into the selected pin. Therefore it is negative at the emitter, because it flows from there into L2. Look at the collector current and you get a positive current.
ltSpice simulation differences between subckt and schematic? - Page 1
Forum section: electronics / projects

author: Andrew_K
author_rank: Contributor
timestamp: December 23, 2023, 07:42:17 pm
content: I was interested in seeing how LT modeled one of their devices, just for my own learning. So I took the subckt definition for LT1970 and made it into a schematic.The spice netlist matches 1:1 with the subckt definition; Net names, components, models, spice statements, everything. I've checked line-by-line in winmerge.Despite this, I'm getting a huge discrepancy between the behavior of the component subckt placed, vs the schematic I made.Does ltspice handle or simulate subckts differently?

author: KerimF
author_rank: Frequent Contributor
timestamp: December 24, 2023, 12:09:20 am
content: My LTspice (LTspiceIV, version 4.23l) handles the two forms in the same way.You will likely find out a minor difference, in the least, between your schematic and of the subckt one.

author: SiliconWizard
author_rank: Super Contributor
timestamp: December 24, 2023, 12:11:33 am
content: Could you post your .asc file so we can check?
LTSpice simulation of NCS325 autozero op amp fail... - Page 1
Forum section: electronics / projects

author: SilverSolder
author_rank: Super Contributor
timestamp: March 07, 2020, 02:16:48 am
content: I found a Spice model for the NCS325 on ON Semiconductor's site... imported it into LTSpice... but it fails with an error message:Analysis: Time step too small; initial timepoint: trouble with node "u1:21"What could be going wrong here? I feel as if I've tried everything, but there must be something fundamental I'm overlooking...
ltspice simulation problems - Page 1
Forum section: electronics / projects

author: jmelson
author_rank: Super Contributor
timestamp: May 23, 2019, 09:45:30 pm
content: Couldn't find a good place to ask this, if there's a more proper place, let me know.I was trying to simulate some one-shots, tried to add the 74HC4538 to my favorite sim (Protel 99SE) but couldn't get that to work.So, I added the 74HC and everything else model library from texane for LTspice. I threw together a test circuit, but I can't get ANY comparators to work properly. I tried a bunch of LT's own parts, they gave a low DC output. The only one that responds at all is the LM319, but it is VERY weak, only gives nanoamps of output, and it appears to be phase reversed.Here's the schematic file from LTspice:I hope it is obvious what I'm doing wrong, i'm a real neophyte with LTspice.Thanks,Jon

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 23, 2019, 11:25:58 pm
content: You put the libraries where?? What is "ZZZ\\LOGIC\\74HC\\"?Tim

author: jmelson
author_rank: Super Contributor
timestamp: May 24, 2019, 01:49:28 am
content: Quote from: T3sl4co1l on May 23, 2019, 11:25:58 pmThat's where the huge file fromhttps://yadi.sk/d/6nSSUmZiT9oCoQhad all the 74HC stuff I wanted, so I just kept it the same. It does work.It looks like my comparator problems were just that I was making the input pulses too short. Once I slowed down the pulses, it worked, at least using the LM393 comparator. GOOD THING I pressed on and simulated this circuit, as it does NOT work as designed. But, now that I have the simulator actually working, I can try to fix the logic.Thanks,Jon

author: iMo
author_rank: Super Contributor
timestamp: May 24, 2019, 03:08:01 am
content: ZZZ is the Bordodynov library - he created and updates from time to time a large bundle with a lot of components and examples.

author: jmelson
author_rank: Super Contributor
timestamp: May 24, 2019, 05:00:09 pm
content: Quote from: imo on May 24, 2019, 03:08:01 amAnd, it is GREAT! It adds all sorts of jellybean parts to the proprietary LT parts.Jon

author: lordvader88
author_rank: Frequent Contributor
timestamp: May 26, 2019, 04:20:02 pm
content: excellent, I too shall use these files, if i can find install instructions, otherwise it will sit on my drive

author: hugo
author_rank: Regular Contributor
timestamp: May 26, 2019, 05:41:48 pm
content: It's easy to use these files:- use this folder for symbolsC:\Users\Joe\Documents\LTspiceXVII\lib\sym\ZZZ- use this folder for libs and subcktsC:\Users\Joe\Documents\LTspiceXVII\lib\subThis is Bordodynov's home page :http://www.bordodynov.ltwiki.org

author: steve1515
author_rank: Regular Contributor
timestamp: August 04, 2024, 11:16:19 pm
content: I just installed LTSpice 24 and copied the files from Bordodynov's zip file into C:\Users\Steve\Documents\LTspice\lib, but they don't show up when adding a component. Do I have to change any setting in LTSpice's search path?I just have the defaults of...User libraries directory: C:\Users\Steve\Documents\LTspiceSymbol Search Path = <Blank>Library Search Path = <Blank>
LTSpice Thyristor\SCR Library? - Page 1
Forum section: electronics / projects

author: Alex30
author_rank: Regular Contributor
timestamp: August 26, 2014, 09:29:26 am
content: I am just trying to track down a library to use in LTSpice that has some basic thyristors\SCR's. I found this:http://www.littelfuse.com/technical-resources/spice-models/thyristor-spice-models.aspxand a few others but I can't get them to load in LTSpice (I tried adding the library and changing the blank SCR model to reference the library item but kept getting errors).I was wondering whether someone could confirm whether these work for them and how they did it, or whether these don't work, or if someone has a good library of SCR\Thyristors I can use?Thanks.

author: Mj12
author_rank: Contributor
timestamp: August 26, 2014, 03:05:52 pm
content: Works for meI did following: download library fileadd spice directive .lib <path to library file> to your simulation schematicadd SCR symbol from ltspice symbol library right click it and replace the SCR with correct thyrsitor model eg: EC103D1 and then thing should workattached thyristor library and simulation example

author: Alex30
author_rank: Regular Contributor
timestamp: August 27, 2014, 02:55:15 am
content: Okay that's really strange... It will only let me add the library if I save my project into the lib folder, even if I add the directory of the lib into the project using the browse button. Oh well it seems to be working, thanks a lot for taking the time to test that for me!
LTSpice transformer turns ratio - Page 1
Forum section: electronics / projects

author: anishkgt
author_rank: Frequent Contributor
timestamp: September 25, 2017, 03:26:12 pm
content: Hi All,i am trying to add a transformer in LTspice and the turns ratio is something i am having trouble with. In reality my transformer primary is 220 turns and secondary 3 turns of 3AWG wire. In LTSpice how would it go with henry ?

author: anishkgt
author_rank: Frequent Contributor
timestamp: September 25, 2017, 04:08:02 pm
content: never mind, i omitted the transformer, instead used a sine wave signal with 3VAC

author: Kalvin
author_rank: Super Contributor
timestamp: September 25, 2017, 04:14:31 pm
content: For the interested:http://cds.linear.com/docs/en/lt-journal/LTMag-V16N3-23-LTspice_Transformers-MikeEngelhardt.pdf

author: anishkgt
author_rank: Frequent Contributor
timestamp: September 25, 2017, 07:12:06 pm
content: On second thought i just did it and seems to add more sense.
LTSpice - varying frequency along time - Page 1
Forum section: electronics / projects

author: atferrari
author_rank: Frequent Contributor
timestamp: February 14, 2015, 07:32:51 pm
content: LTSpice simulation.I could not find a way to implement this:a) Testing a circuit fed with a fixed amplitude sinusoidal voltage source varying frequency along a certain period. Say, in 2 seconds, between 6KHz to 450 Hz with 0.5 V amplitude.b) Later I would like to test the same circuit in the same period at a fixed frequency with a varying amplitude.c) And last, eventually, mixing both options.Is such a thing possible? I fear I am out of luck here.Please note:I am not trying to do a.tran.acsimulation; my test is inone pass along timeand stepping a parameter is not what I need either (well, the way I know to use it, at least...).Suggestions appreciated.

author: c4757p
author_rank: Super Contributor
timestamp: February 14, 2015, 07:34:35 pm
content: Quote from: atferrari on February 14, 2015, 07:32:51 pmThat's the whole idea of a transient simulation!AC analysis?The alternative it to use a behavioral voltage source and put in the equation for the signal you want by hand. I'd go with an AC analysis though.

author: atferrari
author_rank: Frequent Contributor
timestamp: February 14, 2015, 07:52:05 pm
content: Quote from: c4757p on February 14, 2015, 07:34:35 pmI spent some time reading about the behavioral sources but couldn't come to try anything yet. Any link where to go for read some concrete examples?

author: MrAl
author_rank: Super Contributor
timestamp: February 14, 2015, 07:53:49 pm
content: Hi,There is a VCO in the software. Use a ramp voltage to control it, that gives a frequency sweep unless it has sweep built in.

author: c4757p
author_rank: Super Contributor
timestamp: February 14, 2015, 07:56:36 pm
content: Quote from: atferrari on February 14, 2015, 07:52:05 pmIt's just a source that takes an equation directly. Just put in something likeV=sin((6.28*time*10k) * time)

author: atferrari
author_rank: Frequent Contributor
timestamp: February 14, 2015, 08:32:01 pm
content: Quote from: c4757p on February 14, 2015, 07:56:36 pmThanks for that!

author: atferrari
author_rank: Frequent Contributor
timestamp: February 15, 2015, 07:20:03 pm
content: Quote from: c4757p on February 14, 2015, 07:34:35 pmSorry. You were RIGHT. What I did not want was exactly that:.ac analysis. My bad.
LTSPICE VCVS limits.....? - Page 1
Forum section: electronics / projects

author: Smokey
author_rank: Super Contributor
timestamp: September 29, 2015, 12:05:39 am
content: I'm having a hell of a time trying to put voltage limits on a voltage controlled voltage source. According to the following link there are parameters for Min and Max for the E VCVS but I can't get LTSPICE to work with them.http://www.ece.uci.edu/docs/hspice/hspice_2001_2-206.htmlI just get an "unknown paramater" fault.I would post an asc file, but it's not even a circuit yet, just an E VCVS. It works as expected, just not with limits.Any ideas?

author: Smokey
author_rank: Super Contributor
timestamp: September 29, 2015, 12:41:24 am
content: I'm just going to update this real time as I find stuff. Here is the LTSPICE wiki page for VCVS. Looks like LTSpice doesn't support min and max for VCVS. Interesting they recommend using a VCCS and shunting it with a resistor to make a voltage. Going to try that now.http://ltwiki.org/index.php?title=E_Voltage_Dependent_Voltage_Source

author: Smokey
author_rank: Super Contributor
timestamp: September 29, 2015, 12:54:46 am
content: Looks like the same deal with no limits on VCCS. I think I have a workaround now that current limits and diode clamps the output of the first VCVS, and feeds that voltage into a second VCVS as a buffer. That just seems silly.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 29, 2015, 01:49:49 am
content: This is probably more along the lines of what you want;http://ltwiki.org/index.php5?title=B_sources_(complete_reference)

author: Smokey
author_rank: Super Contributor
timestamp: September 29, 2015, 02:26:04 am
content: Damn. That is one seriously intimidating spice source. I love how it's super complex and they don't give any examples. What do they think I am, an engineer???
LTSpice: Why does my circuit stop working when I swap op-amps? - Page 1
Forum section: electronics / projects

author: TimNJ
author_rank: Super Contributor
timestamp: November 16, 2016, 09:46:29 pm
content: Hi all,I'm developing an ECG/EEG front end in LTSpice right now. (This is for my senior design project. I've asked a few questions before which you all have had wonderful answers for. Thanks!)The final step in the circuit is an analog level shifter to convert from bipolar to unipolar for the ADC. For this, I determined I needed a rail-to-rail op amp to operate near the upper supply rail (3.3V). Before that, I was using the LT1114 across the board and everything worked fine.I can replace U4 with an LT1884 with no problem, but replacing U2 or U3 causes the circuit to completely fail. My sine wave test signals basically go completely flat (DC)...What could possibly be going on here? I thought the specs between the LT1114 and LT1884 were comparable so I'm a little lost.http://cds.linear.com/docs/en/datasheet/111214fb.pdfhttp://cds.linear.com/docs/en/datasheet/1884fs.pdfAny insights? Thank you!

author: snarkysparky
author_rank: Frequent Contributor
timestamp: November 16, 2016, 09:56:10 pm
content: Quick glance but I don't see any feedback from output to input on the block amplifier.If that is not an issue check the bias current. One amp is pulled to ground with a large resistor. The bias current for one amp could be causing it to rise from ground.

author: TimNJ
author_rank: Super Contributor
timestamp: November 16, 2016, 10:04:54 pm
content: Quote from: snarkysparky on November 16, 2016, 09:56:10 pmWow...thank you. I have no idea how this circuit was working before...My inverting and non-inverting inputs flipped for both U2 and U3. Thanks! Case closed.
LTV-846 & ATMega Port - Page 1
Forum section: electronics / projects

author: Quarlo Klobrigney
author_rank: Super Contributor
timestamp: December 08, 2021, 06:50:04 am
content: LTV-846 & ATMega Port or what stupid thing am I doingI have a 12VDC source feeding the diode input to an optocoupler via a 560Ω resistor.The diode cathodes to ground.The input to the AVR ports are inputs and their prospective pullups are on.The emitters of the opto transistors go to ground. The same common ground as the AVR.What I seeis 12VDC on the port inputs!WHY???

author: jwet
author_rank: Frequent Contributor
timestamp: December 11, 2021, 04:00:57 am
content: The ground for two sides shouldn't be shared- this is whole idea of an opto isolator. The LED cathodes on the left should all return to the 12V supply. The emitters on the right should all return to your micro controller ground. The only coupling should be the photons that are lighting up the transistors. The ground of your 12V system has no relation to the ground of your AT Mega. This is exactly why optocouplers are useful, they can bridge different ground domains. Their isolations specs (5000V for the LTV-846) is the difference in ground that they can handle. With the two grounds tied together, you're defeating the purpose of having an opto coupler.
Lucky Catch!! - Page 1
Forum section: electronics / projects

author: mawyatt
author_rank: Super Contributor
timestamp: February 24, 2025, 01:44:21 am
content: Caught this cheap puppy before it decided to loose it's top (note the bulging)Supposed to be a 220uF 25V Cap, but MD-1 Tweezers measures ~12uF with ~25Ω ESRWas in a piece of custom circuitry (Ref Voltage) that has been running a few years 24/7Best,

author: Simmed
author_rank: Frequent Contributor
timestamp: February 24, 2025, 02:08:41 am
content: chengx !
Lumineq EL640.480-AF1 VGA display - Page 1
Forum section: electronics / projects

author: LukeW
author_rank: Frequent Contributor
timestamp: September 16, 2018, 04:37:22 am
content: So, I've got one of these monochrome EL displays pulled out of an industrial controller.https://beneq.com/sites/default/files/product/fields/field_operating_manual/operation_manual_el640.480-af.pdfThe 20-pin connector has 8 bits of data (5V levels), a few control lines, and a 5V 75mA and a 12V 700mA supply.The display is stuffed, and I'd like to buy a new one that doesn't break the bank.Alternatively, I'd like to build an adapter that brings out this video interface (from the proprietary machine controller board, which I don't have schematic/documentation for) and convert it to VGA video or something like that, analog video, allowing an improvised replacement of the special monitor with a standard monitor.Any ideas?
Luminook - Roll your own - Page 1
Forum section: electronics / projects

author: nicknails
author_rank: Regular Contributor
timestamp: May 15, 2020, 05:03:33 pm
content: I found Luminook through a facebook link and I like the idea of it, but it's not available until October and only through indiegogo, which I don't trust.I want to make one myself and I don't think it should be all that hard. Pretty much need some sort of battery pack and either a motion sensor or a door switch sensor.Can anyone offer suggestions on how I would do this? I don't have an issue soldering, but I would want the solution to be clean and tidy.

author: Marco
author_rank: Super Contributor
timestamp: May 15, 2020, 08:05:33 pm
content: Are you really ever going to bother recharging that? Pull a mains wire.With mains and for a magnet sensor, you could get a Meanwell PWM power supply, an USB power supply and a hall effect switch like the A3144. Use the hall effect switch to turn on the PWM power supply via it's resistance dimmer input, add a resistor or potentiometer to set intensity to your liking.Although I'm sure there's commercial all in one systems for that too.

author: thm_w
author_rank: Super Contributor
timestamp: May 15, 2020, 10:59:22 pm
content: Looking at the kickstarter page:- "activated automatically by the position of the door. you decide where in the travel" - analog hall sensor or IR distance sensor- "turns off on a timer or when walking away" - timer with microcontroller, when walking away would require a IR or similar motion sensor.If you don't care about those features then a simpler hall switch or reed switch would work, triggering a mosfet or supply as marco suggested.10ft LED strip, lets say 5W per meter = 15W. So if you run the thing off two 18650's (20Whr) it will last 1.3hrs. Maybe a few weeks worth of use?
Luminor Electroluminescent paint - Page 1
Forum section: electronics / projects

author: sixtimesseven
author_rank: Frequent Contributor
timestamp: November 21, 2018, 09:08:18 pm
content: Applied science just posted a vid on electroluminescent paint:https://youtu.be/eUUupR-ongsReally interesting stuff. But the paint from Luminor is rather expensive for hobby use. Does anyone have a source for a cheaper alternative / smaller package size to recommend?Who already did projects with that stuff?
LumiWatch Projection Watch - Page 1
Forum section: electronics / projects

author: EEVblog
author_rank: Unknown
timestamp: April 23, 2018, 11:35:02 pm
content: Another attempt at a projection watchThey are calling out Captain Disillusion on Twitter, because they have a real prototype.I don't see this tech is every going to be a practical project someone is going to want to use.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 24, 2018, 03:56:02 am
content: I remember a laser keyboard that projected a keyboard onto the table or whatever surface you set it on.

author: EEVblog
author_rank: Unknown
timestamp: April 24, 2018, 05:15:54 am
content: Quote from: NiHaoMike on April 24, 2018, 03:56:02 amYep, but that benefited from a much higher projection angle, and a known flat stable surface.Having it in a watch at a shallow angle on an irregular surface that moves is always doomed to failure.Of course it's fun to play with such tech, but it will never be practical.

author: Gyro
author_rank: Super Contributor
timestamp: April 24, 2018, 08:59:58 am
content: I notice that he doesn't have any hair on his arm. Maybe it'll be necessary to include a waxing kit?

author: mikerj
author_rank: Super Contributor
timestamp: April 24, 2018, 11:15:50 am
content: Quote from: Gyro on April 24, 2018, 08:59:58 amI'm thinking a small arm mounted projection screen would be more useful
Lure coursing machine for whippets - Page 1
Forum section: electronics / projects

author: yendrzei
author_rank: Newbie
timestamp: July 26, 2025, 07:24:08 pm
content: Hello everyone,I’m looking for help designing and building a lure coursing machine for whippets. I came across the MagDog Pro (24 V, 200 m line) on TopDogStore, but given the size of the teaser, its weight, and the rough, dense grass terrain, it won’t meet my needs. At competitions they use a lure weighing about 200–300 g over a course of 700–800 m, whereas the MagDog Pro only handles 200 m.My requirements and design goals:- a 200–300 g lure suitable for uneven, dense grass terrain- at least 400–500 m of line- lure speed of at least 60 km/h, ideally 80+ km/h- total device weight under 10–12 kg for easy portability- speed control via RC transmitter or throttle- bidirectional motor operation (winding/unwinding)- an emergency STOP brake in case the dog grabs the lureSo far I’m considering these components, but would appreciate your expert advice:- Motor: Flipsky BLDC Belt Motor Battle Hardened 6354 170 KV 2450 W or Flipsky 3625 1800 KV 1800 W- ESC: from budget ($30) to professional ($130) – not sure which to choose- BMS / Battery: would a 6S LiFePO₄ pack be suitable? What capacity and discharge current do I need?- Control: recommendations for an RC transmitter/receiver or throttle- Display: a voltage/battery-level monitor moduleAny suggestions for specific motor models, ESCs, batteries, BMS, control electronics, and assembly tips would be greatly appreciated. Thanks!

author: mr ed
author_rank: Regular Contributor
timestamp: July 28, 2025, 11:29:23 am
content: Consider a medium sized drone? Automate the course path with custom sw. Drags the lure. 800m of line seems difficult.
Luxo KFM LED Lamp take apart question - Page 1
Forum section: electronics / projects

author: rodorr
author_rank: Newbie
timestamp: May 05, 2018, 04:29:10 pm
content: I just purchased a Luxo KFM LED magnifying lamp (model number: KLM026025) and it is wonderful for electronics work, I love it. My only complaint is that I purchased the one with a 5 diopter lens and I think a 3 diopter lens would be a better solution. I purchased a 3 diopter replacement lens to change it over. The Luxo lens/lamp head has 4 hex screws that come apart easily but it has one other keeper at the front of the lamp that has a small access hole. Does anyone here have an idea as to what type and size of keeper this is? It almost looks like a small hex set screw (maybe it is) but I couldn't find anything that seemed to fit. Any help would be appreciated.Thanks,Robert Dorr
LVC driving optos @ 20kHz maximum practical cable length? - Page 1
Forum section: electronics / projects

author: Jester
author_rank: Frequent Contributor
timestamp: September 20, 2022, 01:33:50 pm
content: I appreciate this could be a very fuzzy question......Assume:Driver: 74LVC3G17 (powered with 5V, 24mA drive capability)Max frequency 20kHzCable: twisted bundle of 5x #22 no shield, only one signal (the step signal) is changing.Driving opto-isolator @10ma (stepper drive)Environment: motors, VFD, steppers etc. within 1MAt what cable length, would you expect issues to occur?I'm curious to hear about situations with relatively short cable lengths that were problematic, as well as longer lengths that worked?

author: hanakp
author_rank: Regular Contributor
timestamp: September 20, 2022, 02:17:33 pm
content: There is no universal answer. There are 3 effects to consider:1. Cable capacitance. If it's too high, the driver won't be able to switch on the optocoupler LED fast enough. That can introduce random delays and jitter at the receiving side.2. Cable crosstalk. Pulses on adjacent wires can generate false signals.3. How fast are the signal edges. The sharper the edges are, the worse crosstalk and signal reflections (ringing) become. Excessive ringing can be falsely detected as two fast pulses in succession.How bad they become in practice highly depends on physical construction of the device. Adjacent signal wires with one common return ground is worse, signal-ground-signal-ground is better. Slow edges or reflections can be improved if the receiver has hysteresis. Even changing the cable length a few centimeters can sometimes "fix" problems with ringing, particularly with flat ribbon cables. Modern digital buses are usually fully differential and with controlled impedance, precisely to combat these effects.

author: pcprogrammer
author_rank: Super Contributor
timestamp: September 20, 2022, 02:22:01 pm
content: I did 1 wire protocol (Dallas/Maxim devices) with optocouplers on both ends and it worked up to 90 meters un shielded twisted pair. Did not have more cable, and it was just a single connection on the cable. (ground, signal and 5V)Had to do some signal recovery at the far end. And 1 wire is bidirectional so two optocouplers at each end to make it work.But for your case it depends on a lot of factors, like the cable parameters, what is the interaction between the signals, like switching at the same time, or independent which might give cross talk, switching time, etc.

author: jonpaul
author_rank: Super Contributor
timestamp: September 20, 2022, 02:41:56 pm
content: use CAT 5 or higher grade Ethernet UTP, RS-485 TX,RX, 100m legnth easilySee my AES,SMPTE and NAB papers on digital audio transmissionAlternative is full FO, eg TOS-linkj

author: Marco
author_rank: Super Contributor
timestamp: September 20, 2022, 02:51:27 pm
content: Cable capacitance is not an issue at these speeds, at 1us rise time you're already looking at many 100s of meter.
LVCMOS to CMOS and vice-versa level translatos in DIP? - Page 1
Forum section: electronics / projects

author: satyamfifa
author_rank: Regular Contributor
timestamp: June 07, 2021, 09:45:13 pm
content: Hey All,It is often the case when I am interfacing old digital components such as a ERPOM chips from 80s to new compoenets like FPGA, CPLD, MCU etc that there is a issue to voltage level translation from LVCMOS to CMOS and other way around. I've tried to find several voltage translation chips to solve this issue but I haven't had great luck finding them in DIP. So far what I have come accross is something like CD40109B from Texas Instruments, which doesn't specifically say can translate LVCMOS to CMOS but might do the job looking at the specifications, however it seems to be only low to high level shifter.Therefore it would be nice to know if there is a sollution avaiable specifically in DIP.Kind Regards,Sparsh

author: Zero999
author_rank: Super Contributor
timestamp: June 07, 2021, 09:53:46 pm
content: The 40109 is slow, along with the 4504, which is similar, but with six buffers.https://www.ti.com/lit/ds/symlink/cd4504b.pdfIf you want to go from low to high, the 74HCT series will convert 3V logic levels to 5V. If you want to go from high to low, there's the 74HC4050, which can tolerate 5V on its inputs, when run at a lower voltage. Another option is to just use current limiting resistors, on the inputs to 3V logic, but it will slow it down and you have to be careful, the 3V logic supply voltage isn't pulled up.

author: satyamfifa
author_rank: Regular Contributor
timestamp: June 09, 2021, 03:24:57 am
content: thanks a lot, that's exactly what I was looking for
LVDS clock driver - Page 1
Forum section: electronics / projects

author: xzswq21
author_rank: Frequent Contributor
timestamp: December 26, 2017, 09:03:35 pm
content: HelloI have a LVDS clock and LVDS clock distributerbut there is a problem:when I want to connect the Clock IC to the clock distributer there is a cross path between these components bcoz the P channel of clock distributer is in front of the N channel of Clock IC:P1--->N2N1--->P2now if I want to connect the both P channels to each others I should use a via. (the clock freq is 200MHz)is there any problem swapping P and N in order to make the layout clean?P1--->N2N1--->P2if so there is no need to use any vias.Thanks

author: xygor
author_rank: Regular Contributor
timestamp: December 26, 2017, 09:50:30 pm
content: Should be no problem at all. It just changes the phase from the clock generator by 180 degrees, but the oscillator phase is arbitrary anyway and there is no other path that references it.
LVDS connector identification please. - Page 1
Forum section: electronics / projects

author: djsb
author_rank: Super Contributor
timestamp: August 23, 2023, 05:37:54 pm
content: Before I ask the original vendor of the Newscope-6 display for my HP8563E SA that this cable is attached to, I thought I would ask here. The cable is attached to the pcb on the back of the display using the connector pictured below. The photo is of the end of a spare cable that I have. Is there any information (maybe a data sheet) that shows this connector, and it's mating pcb part? I just want to find out how to replace the existing cable with the spare that I have, and I want to avoid any damage during replacement. Thanks.

author: fchk
author_rank: Frequent Contributor
timestamp: August 23, 2023, 06:50:43 pm
content: My guess: Hirose DF19:https://www.hirose.com/de/product/document?clcode=&productname=&series=DF19&documenttype=Catalog&lang=en&documentid=D31685_en
lvds connector on board analog - Page 1
Forum section: electronics / projects

author: reaper38
author_rank: Newbie
timestamp: July 25, 2016, 12:59:18 pm
content: Hello,Got problem, i have TE Connectivity 2023308-3 40p receptacle on board and i need to connect another board to it, but plug only wire to board 2023314-3, is there any board to board analogs?
LVDS FFC cable impedance - Page 1
Forum section: electronics / projects

author: tmiddlet
author_rank: Newbie
timestamp: November 12, 2016, 03:31:08 am
content: Hello everyone,I'm working on a project where I'm going to need to transmit 16 channels of 1 Gbps LVDS over a short cable.I've been thinking of using one of these Molex cables:http://www.molex.com/molex/products/datasheet.jsp?part=active/0150230251_CABLE.xmlbut I can't find any documentation on them other than a basic drawing.My question is, how should I be spacing the signals and the grounds to get the rated 100 Ohm differential impedance? Clearly G S+ S- G is different than G S+ G S- G in terms of differential impedance.Molex customer support had no idea how to help me on this. Do any of you have experience with this sort of thing?Thanks!
LVDS Interface for AD9789 and DAC advice - Page 1
Forum section: electronics / projects

author: crazymach
author_rank: Newbie
timestamp: February 24, 2018, 03:00:48 am
content: For the AD9789, I am wondering what microcontrollers or drivers are on the market for programming the LVDS interface @ 150 MHz.Correct me if I'm wrong, but aren't LCD's programmed the same way? For example, simple 16x2 LCD's are controlled by 8 data pins that are programmed high and low and the LCD has a built instructions for each command sent? Does the AD9789 have the same instruction sets?http://www.analog.com/media/en/technical-documentation/data-sheets/AD9789.pdfOne other question: So my experience with DACs has been programming the DAC with a value 0-16384 (14 bit resolution DAC) and the output corresponds to the rail's voltage and value programmed. Is this the same case for this AD9789 DAC? If not, can someone advise me with choosing a DAC that has multiple DAC outputs with low update/settling time?

author: dmills
author_rank: Super Contributor
timestamp: February 24, 2018, 12:58:44 pm
content: Ah, no to most of your questions....The 7989 is a **single** current output RF DAC with built in interpolators and up converters/NCOs, this is in no way a simple device.The control registers (Which are extensive) are configured via an auxiliary SPI port completely separate from the main data port.Normal use is with an FPGA or ASIC generating the baseband data and the AD9789 then up converting to the final output frequency from the input IQ streams, most any modern FPGA should be able to drive this thing, and in fact the parallel LVDS is now slightly old school, JESD204A seems to be the modern approach.It actually looks kind of cool, but it is NOT simple to use or to connect (It is in a BGA package).The USP of this device is 4 separate digital processing chains, so you can process up to 4 carriers independently before summing them and driving the single DAC.What does low settling time mean to you? What does multiple outputs mean to you? The usual suspects (TI/AD-Linear) all have parametric search, digging out something that fits should not be hard.