Help Choosing a Simulator - LTspice, QSPICE or TINA-TI - Page 1
Forum section: electronics / beginners

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 05, 2024, 06:56:47 pm
content: One of the areas of knowledge I am looking to expand is the use of a simulator for modeling circuits. I have been playing around with the following 3 simulators.LTspicehttps://www.analog.com/en/resources/design-tools-and-calculators/ltspice-simulator.htmlQSPICEhttps://www.qorvo.com/design-hub/design-tools/interactive/qspiceTINA-TIhttps://www.ti.com/tool/TINA-TII am asking for help in steering my decision-making process. LT Spice seems to be the gold standard but I find it cumbersome to use and the UI not as friendly.QSPICE Was developed by the same gentleman that did LT Spice and seems to be a better evolution of LT spice.For those of you that have read some of my posts before I am somewhat partial to Texas Instruments because I find they make quality parts but most importantly I find it interesting reading their data sheets. Not only do they give specifications but they offer a very good education on certain subject matters. For this particular reason I decided to try TINA-TI.TINA-TI by far to me seems the most natural and easiest to use and model basic circuits.I am asking for people who are a lot more experienced than me to give me guidance in selecting a simulator to focus on. If I decided to settle on TINA-TI would I be missing anything and/or would I be gaining anything over the other two?QSPICE Seems to be superior to LT spice and it was developed by the same gentleman that developed LT spice so naturally it seems like it would be a better simulator.Since I would like to become a lot more proficient in being able to model circuits via simulator and am going to allocate a considerable portion of my time in becoming proficient I am asking for the communities help in guiding my decision making process considering I am virtually new to utilizing a simulator.As always thank you to all who participate in advance.

author: tggzzz
author_rank: Super Contributor
timestamp: February 05, 2024, 07:12:15 pm
content: I suggest the GUI is not particularly important; it is merely visual "syntactic sugar".https://www.techopedia.com/definition/10212/syntactic-sugarMore important:models in the library for the components you want to usewhether the models actually model the characteristics that you need, e.g. noisewhether it can use other standards, e.g. IBIS

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 05, 2024, 08:18:10 pm
content: Quote from: tggzzz on February 05, 2024, 07:12:15 pmI agree with your list but I myself lack the hands-on experience to discern which of the three would be best suited. Are you yourself familiar with any of these products besides LT spice?

author: Zero999
author_rank: Super Contributor
timestamp: February 05, 2024, 09:23:51 pm
content: I've never heard of QSPIC.I've tried TINA-TI, mostly before it was actually bought by TI, but never really liked it. It just didn't seem to work very smoothly and I wasn't keen on the UI. I've also tried it again since TI bought it, but it's still the same.I'd recommend LTSpice. It's pretty easy to import other models into it. If you're going to ask questions here about simulation, you'll generally get better results, if you attach LTSpice files more than any other type.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 05, 2024, 09:28:19 pm
content: Quote from: Zero999 on February 05, 2024, 09:23:51 pmThe proliferation of LT spice definitely is a very strong argument for it. QSPICE was created by the guy that created LT Spice and is supposed to be a much better version of it. I personally don't have the experience or knowledge to confirm or deny that claim but I did do a bunch of research into these simulators.I am surprised you did not like the Texas Instrument UI simulator. To me it is the most appealing and easiest to model with. Just setting up basic DC and AC circuits with random resistor values to practice KVL and KCL is so much easier to me with Texas Instruments.

author: tggzzz
author_rank: Super Contributor
timestamp: February 05, 2024, 09:33:26 pm
content: Quote from: JJ_023 on February 05, 2024, 08:18:10 pmI don't know what models you want and what you want to simulate. If you don't then it doesn't matter which simulator you use; they are all more or less equivalent.Another possibility is microcap; well regarded, but abandonware.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 05, 2024, 09:44:58 pm
content: Quote from: tggzzz on February 05, 2024, 09:33:26 pmMy two main goals for right now are to get a much better understanding of operational amplifiers. I have a few books that are dedicated specifically for operational amplifiers so I am playing around with all sorts of basic operational amplifier circuits.My other main goal is to be able to model the circuits in some sort of spice simulator.Thanks for taking the time to give me your opinion.

author: tggzzz
author_rank: Super Contributor
timestamp: February 05, 2024, 10:14:03 pm
content: What aspects of opamp behaviour, precisely?Some opamp models are so-called macromodels, which model gross large scale behaviour but not the subtle behaviour. For example, they may be suitable for understanding small signal time domain response but not overload recovery nor noise. And that is independent of the simulator: it is only a function of what's in the model.If you are only interested in generic opamp operation, then any simulator will be sufficient.N.B. iMNSHO there is a great deal of value in simulating generic behaviour without worrying about the subtle effects of specific opamp's behaviour. Ditto the subtle behaviour of specific opamps, but that requires detailed accurate models.

author: Zero999
author_rank: Super Contributor
timestamp: February 05, 2024, 10:31:58 pm
content: Quote from: JJ_023 on February 05, 2024, 09:28:19 pmIt's somewhat subjective. I've just downloaded and installed TINA-TI to remind me why I didn't get on with it. Schematic entry is a pain. I have to use the scroll bars, where as with LTSpice it automatically scrolls. The scroll wheel doesn't zoom. If I want to put a resistor in series with something, I have to manually break a wires to place it, then reconnect them. LTSpice allows me to put the resistor on top of the wire and it breaks and remakes the connections for me. When inserting wires, they follow the mouse cursor, rather than going point to point, where I click. Rotating a part with wires connected to it breaks the wires. To be fair, I'm currently running it under WINE and I might've downloaded a slightly older version, as I went to a file download site, as I couldn't be bothered to make a TI account to download it from the TI site, so it might not be quite that bad.Quote from: JJ_023 on February 05, 2024, 09:44:58 pmLTSpice has some handy generic op-amp models which enable you to alter parameters such as bandwidth, open-loop gain, slew-rate, phase margin etc. I've not seen a similar facility in TINA-TI but it might be possible to create your own or even use LTSpice's if you like, although it seems a faff.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 06, 2024, 12:10:32 am
content: Quote from: tggzzz on February 05, 2024, 10:14:03 pmI am just learning the basics with operational amplifiers.The direction I'm looking to go into would be voltage regulation and current regulation for designing a power supply. I have picked out a few chips that are interesting to me that specifically focus on those aspects.Right now I am playing around with the basic operational amplifier circuits that everybody is familiar with when they start.When I am ready to take on my first real project for current sensing I will start a brand-new thread.In my previous posts people suggested modeling stuff in a simulator and I know they exist for a reason and it is one area where my skill set and abilities lack so I figured I would round that out. I usually invest a considerable amount of time into something I want to learn so I want to make sure I pick the right simulator that not only enables me to do what I want but is also intuitive for me to use.I am actually surprised that nobody here seems to be aware of QSPICE since it is supposed to be a direct replacement for LTspice by the gentleman who developed LTspice.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 06, 2024, 12:21:42 am
content: Quote from: Zero999 on February 05, 2024, 10:31:58 pmSo the current version of TINA-TI is Ver 9 (special complementary addition). You know it's funny you mentioned the resistor problem of not being able to drop a resistor and it automatically merges. For me every single component can be dropped in the middle of a wire and it automatically connects.In TINA-TI if you take "operational amplifier" then double-click on it you will have a pop-up window. Look for the row that says "type"and then click on the drop-down menu ( square with three dots) and then you can enter all sorts of parameters.I don't know so you tell me which one has more abilities to tailor a particular operational amplifier?

author: MathWizard
author_rank: Super Contributor
timestamp: February 06, 2024, 12:55:54 am
content: About TINA, do they have most all the TI products in there, but not other companies, much like LTSpice has mainly Linear Technology parts but not much else ?Years ago I used some simpler circuit sims, and didn't like the look of LTS, but now thats all I use. I should use Ki-cad too sometimes, and try TINA, could help for all the common parts not in LTS. People have made some other models tho for common parts, there's some common libraries of other parts. But some models are a bit dodgy, or if not used right like I might be..

author: tggzzz
author_rank: Super Contributor
timestamp: February 06, 2024, 01:27:16 am
content: Quote from: JJ_023 on February 06, 2024, 12:10:32 amThat sounds like a sensible plan in which you will learn a lot.The only point I would add is to avoid jumping into simulation too soon. The first action should be to understand how the standard opamp "design patterns" overcome the inherent variability in practical opamps (e.g. the open loop gain may be 104or 104but the external resistors constrain the circuit gain to be 1 or 10). Make sure you understand the equations that define such operation. Don't forget the phase/frequency Bode plots and how they indicate a circuit's stability (or otherwise!)Afteryou understand how the circuit operates in theory, then jump to simulation in order to confirm and cement your understanding.Any simulator will be sufficient for the above, so choose whichever suits you. They all offer equivalent analysis capabilities, so once you understand the those it becomes trivial to apply the same understanding in a different simulator.The only time you need to go into more detail is when you need to understand whether your circuit will work better with opamp X or opamp Y. At that point you need detailed models usually produced by the manufacturer, and you have to ensure they are sufficiently accurate for your purposes.The big picture is that during a career expect to change simulators multiple times. I started in the1970swith ICAP and ITAP.Exactly the same principles are used now, with astonishingly little change: ICAP is merely "AC analysis", and ITAP is merely "transient analysis".The fundamental input is exactly the same: the ASCII netlists. The only difference is that nowadays a GUI is used to create those netlists, and the outputs aren't ASCII graphs drawn with * and + ! Even today, the netlists are visible, e.g. when you specify/modify a component's values, or set the parameters for an analysis.Summary: just choose a simulator and learn to use it. When beneficial, it is easy to change to another simulator.

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: February 06, 2024, 08:40:43 am
content: The only differences are the user interface and the library of parts, "Spice" is the core engine of all of these.I use LTSpice for Analog Devices parts and Tina for most simple circuits as it seems easier to use. I have purchased the student version of Tina and have used it for several years.SJ

author: Ian.M
author_rank: Super Contributor
timestamp: February 06, 2024, 08:52:24 am
content: Historically, LTspice was preferred on the sci.electronics.* USENET groups, because it was free and its schematics and symbols were ASCII text files, so could be pasted inline in posts, (most servers back then rejected MIME and other encoded attachments in non 'binaries' groups). This resulted in a large user community and a lot of third party models, many developed by experts in their field. The user community has continued to grow. Its still one of the best options for sharing electronic circuit ideas on forums like this one even though its UI is a bit clunky.

author: magic
author_rank: Super Contributor
timestamp: February 06, 2024, 09:37:03 am
content: Quote from: JJ_023 on February 06, 2024, 12:10:32 amThere is a thread about QSPICE and I'm pretty sure most names appearing in your thread also appeared there, so people are aware. But QSPICE has only arrived a few months ago, AFAIK it is not a drop-in replacement for LTspice (it won't open your existing LTspice schematics), it didn't work on Linux last time I checked, and most long time users of other simulators probably haven't had much reason to try it yet.If you feel like being a guinea pig or there are particular things about it that you already know other software can't provide, go for it.I use LTspice because it seemed to be the most popular option a few years ago and it's not too bad. It can run PSPICE models of TI chips available from ti.com, so that's not a problem. OTOH I'm not sure if there are any models of Linear parts that can run under simulators other than LTspice.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 06, 2024, 05:39:50 pm
content: Quote from: MathWizard on February 06, 2024, 12:55:54 amI honestly don't know how to answer your question because I am not overly familiar with TINA. I think it is primarily Texas Instruments based on what I can tell. For example under operational amplifiers there are roughly 100 options.I like Ki CaD for circuit design. I think it's fairly intuitive. As far as their simulator I am not too keen on it but then again I haven't spent a lot of time with it in that regard.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 06, 2024, 05:48:38 pm
content: Quote from: tggzzz on February 06, 2024, 01:27:16 amThank you for such a detailed response. At this point I think I understand the basics of operational Amplifiers. I usually don't struggle with equations or math so I feel I can grasp that fairly well.I have also played around on bread boards with basic operational amplifier circuits, stuff like inverting and noninverting and creating different gains.While researching LT spice I know it is possible to import models from different manufacturers as well as writing your own models I am not sure if it could be done with the other two simulators ( my gut feeling is that you can with QSPICE and I have no good feeling about the Texas Instruments product). Since I prefer Texas Instruments for my components I guess in that regard TINA is a lot more helpful.The reason I am trying to learn a simulator is because it has been recommended by numerous people on this forum. I usually follow the advice of recommendations unless I have a valid reason not to follow them based on knowledge of the subject.

author: watchmaker
author_rank: Unknown
timestamp: February 06, 2024, 05:50:44 pm
content: Have you looked at Multisim Live? It is subscription based which has advantages and disadvantages. But it is very intuitive.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 06, 2024, 05:51:28 pm
content: Quote from: Solder_Junkie on February 06, 2024, 08:40:43 amThank you for your input. I am aware that they are all built on the "Spice" model. I agree with the user interface being simpler on TINA.I have a few questions for you in regards to TINA.What is the main difference between the purchased version that you have and the free download version?Are you able to import components from other manufacturers?

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 06, 2024, 05:58:05 pm
content: Quote from: Ian.M on February 06, 2024, 08:52:24 amThat is such a valid point that you make. I personally dislike the user experience with LTspice. But I am aware that they are probably the most prolific simulator out there which is why they have a large community and third-party models.Since LTspice has been improved upon tremendously by the original developer of LTspice is why I looked into QSPICE. I can't really comment on QSPICE because I have not spent enough time with it to be able to discern whether I enjoy it or not. TINA on the other hand just seems to be a lot more intuitive and easier to use for simple circuits. I don't know how it would model more complex circuits as I don't have that experience yet.The reason I am asking all of these questions is because when I get into something I like to spend a lot of time gaining knowledge and experience to a high enough level. What I don't want to do is become proficient in something that might be either outdated or will limit me in the future.What I am doing is gathering bits of data from people such as yourself as data points to help me make a educated guess as to which one to focus on.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 06, 2024, 06:03:56 pm
content: Quote from: magic on February 06, 2024, 09:37:03 amThank you for your input. I agree with what you are saying on LT Spice.QSPICE, My thinking there is as follows. The guy that created LT Spice is clearly good at what he does. So when he created QSPICE I am sure he implemented things that he felt he missed in the original design. I'm sure if you look at some of your projects or circuits that you built in the past if you had a chance to do them over with the experience and knowledge that you have now you would probably make improvements. That is the reason why I am considering QSPICE.From what I understand you can run Linear parts on TINA. I noticed a linear section on one of the drop-down menus for operational amplifiers. I am not sure if that Is relevant to your point.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 06, 2024, 06:11:01 pm
content: Quote from: watchmaker on February 06, 2024, 05:50:44 pmThanks for the suggestion. I have looked at it although I have never used it. I have reservations about it. One of which being a subscription model. I would much rather pay a couple hundred dollars for a piece of software and be done with it.I also think it is on the fringe of the simulator market which means it's probably not going to have as wide a support base for third-party modeling or development.I also don't know how robust the modeling that simulator is capable of. So even though I am doing very basic stuff now when I go to design some of the operational amplifier circuits in the near future I want to be able to model the exact component, I believe all three of the simulators that I am considering will allow me to do that.I am not sure if it is a standalone model or if it's cloud-based. I prefer standalone.Maybe you could share some insights as to why you like it?Have you tried other simulators?If you have what are your thoughts on them?

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: February 06, 2024, 07:39:55 pm
content: “ I have a few questions for you in regards to TINA.What is the main difference between the purchased version that you have and the free download version?Are you able to import components from other manufacturers?”———-The free version (Tina-TI) is not quite the same as even the lowest cost Student version (around €49), models are not necessarily interchangeable between them, I think Tina-TI is based on an early version of Tina.I have only created basic component macros in Tina -a couple of transistor types that were not listed.Last year I used LTSpice for the first time as I needed to resolve a design problem with an Analog Devices power supply protection IC (an LTC4368), not surprisingly there was not only the macro for the IC, but an instantly drawn complete circuit for it from the datasheet! In addition, when I asked Analog Devices about the problem they suggested a fix… not only was it fixed in the simulation, it was fixed in the actual circuit too.It’s horses for courses, use LTSpice for Analog Devices chips and maybe Tina for Texas Instruments ones as well, if you like. I prefer the UI of Tina, but I am more familiar with using it. Tina appears to have some big name supporters in the training side of industry as well as education.SJ

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 06, 2024, 08:14:55 pm
content: Quote from: Solder_Junkie on February 06, 2024, 07:39:55 pmThanks for clarifying all of that.

author: watchmaker
author_rank: Unknown
timestamp: February 07, 2024, 01:47:49 am
content: I really am a beginner.But I have tried to make Spice for TI, Tina, Microcap and Kicad work. As well as LtSPICe and Multism 17. I forget which one, but one of those damned programs makes wiring components together waay too hard.I do not plan on doing PCBs, so my main interest is simulation to support my learning resources and breadboarding.I use Multisim a bit but bear in mind I am just starting capcitors and opamps via the Real Analog vids. Once I figured LtSpce was shortcut driven, I started using it too. Have not yet decided.Of all the ones I tried, MultiSim live is the most intuitive. Just sat thru the webinar today and I had already earned most of what I needed.Yes, it is cloud based and subscription. The free subscription is very limited. I am trying to see if it makes Multisim 17 more understandable. I am not the one to evaluate how limited the other MS Live subscriptions are for serious work. But I can see being tempted to go to the first tier as I progress.Given that we have to pay for new versions after a couple years, it may not be a bad deal.I still have my PC based photo programs and libraries though. And I store nothing on the cloud except the business files I share with customers. I never believed that the keepers of the cloud would not poach what was uploaded.

author: RoGeorge
author_rank: Super Contributor
timestamp: February 07, 2024, 02:37:35 am
content: My favorite is LTspice. Easier to use than any other simulators I've tried, and backward compatible with most other spice versions. There are models online for almost anything. Very popular, large community, easy to find online answers for any problem, plenty of tutorials, books, videos, etc. Very well maintained by top professionals (Analog Devices) and often updated, rock-solid and no bugs, works with Windows, Linux (through WineHQ), Mac, easy to share schematics (attach the .asc text file), free for personal/home use with no performance limitations, no ads, no buy-me nagging, can be called from Python to automate schematic creation/run/results postprocessing, works entirely offline, doesn't expire and doesn't need any license or account. Probably the best SPICE out there. Highly recommended.Sometimes I also use QucsStudio, because it has live sliders to adjust components values, like this:though, QucsStudio is almost unmaintaned (one developer), and the GUI style is from QUCS, so more cumbersome, even more cumbersome than TINA-TI.Whichever you'll choose, don't expect them to be intuitive, or eye candy. That's valid for any CAD/EDA program, in general. They all require some learning, then practice. It's a steep learning curve, but once one is fluent with a simulator, that will be an invaluable skill, particularly for learning, and later for design.

author: LinuxHata
author_rank: Frequent Contributor
timestamp: February 07, 2024, 04:34:07 am
content: Can't say anything about another two, but LTSPICE is awful - these guys have no understanding of the term ergonomics, and software appears to be designed for IBM System/360 and to be used with light pen and keyboard - absolutely not mouse friendly. Not mentioning that resistors are in zigzag shape and many common components are missing right out the box (triacs, for example) and you have to search, download and install separately.Also, it does not considers limit of the components - say, if using some DC-DC boost converter, which can only work at 5V input and 2A current, it will simulate it working at 100V input voltage and 100A output current (as example) and won't give any errors.

author: magic
author_rank: Super Contributor
timestamp: February 07, 2024, 07:50:03 am
content: Perfectly usable and effective with a mouse and keyboard, I don't get what you are talking about.The latter complaint is against chip models, same model will simulate the same on other engines.SPICE simulators in general don't account for limits of discrete semiconductors either.

author: RoGeorge
author_rank: Super Contributor
timestamp: February 07, 2024, 08:23:07 am
content: LTspice is a CAD/EDA tool, don't expect it to be as easy as a videogame. Of course it has both types of resistors, rectangle for European style drawing of R, and zig-zag for American style (default, but can be changed).LTspice is for productivity and heavy lifting, not for glitter and eye-candyness. Requires one to learn how to use the tool first. Requires one to make intensive use of 20-30 keyboard shortcuts at least, to make the drawing and handling easy. Shortkeys are programmable, make them single press and easy to remember. Avoid keyboard alterators (not CTRL+something), use single letter shortcut keys, it's easier to touch a key than to press a CTRL+something else. For example I use 'M' for move part and 'D' to drag a part with its wired attached, etc.If you think LTspice is cumbersome, then name a better simulator.

author: tggzzz
author_rank: Super Contributor
timestamp: February 07, 2024, 09:31:34 am
content: You don't understand several important points.Quote from: LinuxHata on February 07, 2024, 04:34:07 amCorrect, but it is not limited to IBM360s. I first used a Spice on a Honeywell DDP516 minicomputer. Spice, per se, has changed little since then.Spice input and control statements are ASCII text. Spice output is tables of numbers, and graphs drawn with ASCII characters similar to this (but normally the graph would go down the pages, not across)QuoteThat's a standard. Ditto inductors being "curly". The nice thing about standards is that there are so many to choose from.Besides, that is merely "syntactic sugar", equivalent to obsessing about what fonts are used.QuoteHave you come across the concept of a library being separate from a language and an execution engine? That has many many significant advantages.QuoteCorrect; it will also allow you to pass 1A through a 1Gohm resistorThat is nothing whatsoever to do with any Spice.That happens with every single Spice component: they only model reality, and omit significant behaviour. For example the Gunnel-Poon BJT model doesn't correctly model low currents.You always need to assess what aspects of behaviour are important for your task, and then to validate how well the models represent reality.

author: tggzzz
author_rank: Super Contributor
timestamp: February 07, 2024, 09:34:45 am
content: Quote from: RoGeorge on February 07, 2024, 08:23:07 amPrecisely. Should be emphasised.QuoteOh, it is cumbersome.But underneath all the simulators are the same. Component models.... no so much!

author: MathWizard
author_rank: Super Contributor
timestamp: February 07, 2024, 01:09:40 pm
content: A lot of times using LTS I'll be unfamiliar with the computer science behind the scenes, and most guides probably expect you do know the names of stuff and equations, and the correct computer syntax.I run into the same thing when using Octave, the math program. I need some basic computer science guide just aimed at math.

author: RoGeorge
author_rank: Super Contributor
timestamp: February 07, 2024, 01:26:16 pm
content: Quote from: MathWizard on February 07, 2024, 01:09:40 pmNot at all. It's only mouse drawing and clicking the right buttons to run a simulation. Then, after the simulation ended its calculations (sometimes instant, other times can take a few seconds or minutes at most), click with the mouse inside the schematic and the waveform at that point will appear plotted in the plots window.The graphic schematic is stored internally as a .asc text file. Under the hood all is text files, and there is indeed a syntax for the schematic drawing, and for the netlist if you want to tinker with that manually, but it is not needed at all during normal use.It's all graphical drawing, click run, then click inside the graphical drawing to see the waveforms.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 07, 2024, 02:57:29 pm
content: Quote from: RoGeorge on February 07, 2024, 02:37:35 amThank you for the elaborate explanation of your viewpoint. I was aware of most of the positive attributes of LT Spice. That is the primary reason why I am considering it.QSPICE seemed to me as an evolutionary product as it was developed by the gentleman that developed LTSPICE which is the reason that I am considering it. It is supposed to be much more robust but currently lacks the user base that LTSPICE has and with it the benefits of having a large user base.I chose TINA because as you know I have a partial bias towards Texas Instruments and its components as well as the well-written support of literature for them as well as many other generalized topics. I figured Texas Instruments probably puts out a decent product and would be preloaded with the models of the actual chips that I would consider experimenting with.I know that simulators aren't easy to grasp. I am fairly proficient in several CAD packages so I know what that process entails. This is the reason why I am trying to make the proper decision so as not to waste time on a simulator that will be not the best suited for me.The one point where I do disagree with you is that the UI is fairly important. For example in your video it would be nice to have sliders on resistors and capacitors. There actually is a really neat very basic simulator that has all of that in case you are interested.It is fairly limited in its capabilities compared to the simulators discussed here.https://www.falstad.com/circuit/circuitjs.html

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 07, 2024, 03:00:07 pm
content: Quote from: LinuxHata on February 07, 2024, 04:34:07 amI agree with your first Statement of the simulator being terrible in terms of user interface. It is one of the reasons I am trying to explore other alternatives. However what I am finding out is that because of its prolific user base that it is hard to discount in terms of consideration.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 07, 2024, 03:07:53 pm
content: Quote from: tggzzz on February 07, 2024, 09:31:34 amHave you personally played around with QSPICE? I don't have the experience nor knowledge base to personally make the statement, but from what I have researched and learned about it is it is supposed to be a much more robust simulator. It was developed by a gentleman who developed the original LT Spice. There is a interview video with him that I watched where he touted some of the benefits. Unfortunately my knowledge base and experience prevents me from fully understanding his arguments.

author: Terry Bites
author_rank: Super Contributor
timestamp: February 07, 2024, 03:30:54 pm
content: All spice lies!As ever, you get what you pay for, if you dont pay don't expect the best of the best.LTspice is not gold standard. Its good enough for most purposes though.Pspice say they are gold standard but you'll have to pay to find out.You may like to check this page.https://electronicsguruji.com/best-circuit-simulation-software/Qspice is more modern and has a more rational interface, it has a deep and easily updated model library.Spice from TI AD etc are also there to promote their products, so they're not entirely a free gift.I still have a (fading) preference for MC or "microcap" because of its superior schematic input. Its old and out of date like me though.Its hard to find but I recall there is a download link on eevblog somewhere

author: RoGeorge
author_rank: Super Contributor
timestamp: February 07, 2024, 03:49:39 pm
content: Quote from: JJ_023 on February 07, 2024, 02:57:29 pmIndeed, and it has. A slider can be attached in QucsStudio for any numerical value (including the values of Rs or Cs) by simply clicking the wanted component, or the wanted parameter, and a new slider will appear.There is another former commercial-only simulator, now freeware by the kindness of its author(s), to whom I would like to thank you very much. It is called Micro-Cap, and has the sliders feature, too, though it was announced there will be no future versions or updates for Micro-Cap.https://en.wikipedia.org/wiki/Micro-Caphttps://archive.org/details/mc12cd_202110<- download linkMicrocap is well polished, has tons of features, and more robust than QucsStudio, but I didn't have the time to play with it yet. It was made for Windows, but it works in Linux, too, through WineHQ. Microcap is based on the SPICE engine, while QucsStudio is based on QUCS. (Component models are different between SPICE and QUCS).https://www.eevblog.com/forum/eda/qucs-qucs-s-and-qucsstudio-simulators-are-not-the-same-thing/QUCS type of simulators also have some RF (Radio Frequency) oriented simulations that are missing from SPICE-like simulators (for example RF filters, Smith charts, etc.).TINA-TI is based on the SPICE engine, just like LTspice, therefore the same spice models for components can be used in either of them. However, different implementations of SPICE-like simulators are using different math solvers (for the same component models), and sometimes the same schematic might work very well in LTspice and not so well in TINA-TI, or the other way around.QSPICE is very new, I didn't use it, but my understanding is that QSPICE has a single developer (at least for now), so it will be hard to beat a full team of programmers backed by huge companies like Texas Instrument, or Analog Devices.Since you use mostly TI parts, TINA-TI is the best choice, indeed, though TINA-TI seemed to me really difficult to work with, by comparison with LTspice. IIRC TINA-TI is based on a commercial version of SPICE called pspice, though I've used pspice during the university years, and the pspice version from some decades ago was a breeze to use by comparison with the current TINA-TI. No idea why TI made a pspice-like simulator so difficult.

author: tggzzz
author_rank: Super Contributor
timestamp: February 07, 2024, 05:22:05 pm
content: Quote from: JJ_023 on February 07, 2024, 03:07:53 pmNo, I haven't.From memory (quite possibly faulty), that developer parted ways with his employer in ways that weren't perfectly amicable, and this caused disquiet in the LTSpiceusercommunity. The reasons were mentioned, but I don't remember them because they were uninteresting.He then developed QSpice, but quite reasonably it isn't free (beer or open source). I haven't bothered to assess QSpice nor the libraries of components.

author: tggzzz
author_rank: Super Contributor
timestamp: February 07, 2024, 05:25:50 pm
content: Quote from: Terry Bites on February 07, 2024, 03:30:54 pmIt is a truism that "All models are wrong, but some are useful"https://en.wikipedia.org/wiki/All_models_are_wrongQuotePaying more does not imply something better,andpaying less does not imply something worse.

author: alligatorblues
author_rank: Regular Contributor
timestamp: February 07, 2024, 05:31:19 pm
content: Quote from: JJ_023 on February 05, 2024, 06:56:47 pmYou'll find, like many other things, design the circuit comes before simulating it. You don't use a debugger to learn how to program. Command driven operating systems are so much faster than gui OSs, but you have to take a few days to learn the commands.I never debug a program as a trial and error method to write correct code. Nor would I use a GUI text editor. I use a command line stream editor called 'sed'. You just type a command line to edit a file the way you want, and redirect the output to a new file. That way, if you've got 1,000 '#' you have to remove and replace with '!', it takes about 2 minutes. Doing it with a mouse and keyboard would take hours.Using a command, I can search 10,000 files for keywords, phases, or the inverse. I can let malware loose, insert my CD-ROM with known good commands, and use 'find' to find every file that has changed attributes in the last 5 minutes. Then I know which files to move into a quarantine, do a hex dump on, and analyze with other tools.It's the same way with electronics, except your tools are mathematics. You can shave 90% of the design time by designing the circuit first, and then simulating it. The simulator doesn't tell you exactly why a circuit won't work. But, since no op amp is ideal, certain tricks must be employed to get them to settle down. And, no circuit ever lives up to the designers hopes.There's a rule of electronic cicuits: "it's easy to get what you don't want, and difficult to get what you do want."

author: switchabl
author_rank: Frequent Contributor
timestamp: February 07, 2024, 05:39:50 pm
content: Quote from: tggzzz on February 07, 2024, 05:22:05 pmIt's not open source but it seems to be distributed by Qorvo for free (after registration). And it looks like the license doesn't have the infamous LTspice non-compete clause. The lack of AD/LT libraries is going to be a big downside for many people though.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 08, 2024, 03:03:03 pm
content: Quote from: Terry Bites on February 07, 2024, 03:30:54 pmThank you for your overview. The link was helpful as it provided additional simulators I was not aware of.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 08, 2024, 03:15:36 pm
content: Quote from: RoGeorge on February 07, 2024, 03:49:39 pmAgain thank you for writing such a detailed response. I was wondering what your thoughts are on this particular video on QSPICE.I like the ability to write the parameters directly on the schematic. I also like the fact that it provides syntax for some of the parameters. I've done a decent amount of coding and it just seems intuitive in that regard.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 08, 2024, 03:20:06 pm
content: Quote from: tggzzz on February 07, 2024, 05:22:05 pmI downloaded it a few months ago and as of that time it was free. I also updated it yesterday and that was free.I think all you need to do is register and verify your email.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 08, 2024, 03:26:39 pm
content: Quote from: alligatorblues on February 07, 2024, 05:31:19 pmThat is an insightful way of looking at it. I have done a decent amount of coding so I understand what you are inferring. Maybe my thought process is off but I looked at the simulator as the development environment and not a debugger.It's also been mentioned that bread boarding is horrible and using a simulator to explore certain basic concepts seems like it would be beneficial. All of the measuring tools are right there. Even though I have an oscilloscope it is just so much easier if I am exploring a basic concept to do it in the simulator.Having said that I am also very aware that getting the circuit to work in a simulator does not guarantee that it will work once put together. Right now I am not designing anything overly complex it's more about putting what I learned into a practical application because then what I read sinks in a lot deeper.

author: RoGeorge
author_rank: Super Contributor
timestamp: February 08, 2024, 07:06:36 pm
content: Quote from: JJ_023 on February 08, 2024, 03:15:36 pmThe GUI looks a little nicer, but nothing that LTspice can not do, or doesn't have. Anyway, wanted to give Qspice a try in Linux. He lost me at the checkbox "I agree to accept spam emails with your ads", which is a mandatory checkbox in order to download. Then it wanted to send me an email with a download code, etc, etc. Not for me.Another thing, may I kindly ask you a personal favor, please? Please stop saying how much you appreciate whatever I might have wrote, each and every time I post something in your threads. This is distracting and awkward already.If you noticed, in general we all here on EEVblog are making comments and statements about whatever the topic is, not about each other. I hope you don't mind asking from you this little favor for myself, and also thanks for all your thanks.

author: twospoons
author_rank: Frequent Contributor
timestamp: February 08, 2024, 09:22:01 pm
content: My personal favorite is Simetrix. I find the UI fairly intuitive, adding models is incredibly simple (drag and drop), and it seems to be quite fast. The free version is node-limited, but its enough for most simple stuff. I've done a small chip design with the free version that had 23 mosfets in it. I'm very tempted to buy the full version, but I seldom run into the node limit so its hard to justify the spend.Tried LTSpice and hated the UI, found it a bit slow to simulate too. Tried TI-TINA, but struggled when I need to use other manufacturers parts.

author: tggzzz
author_rank: Super Contributor
timestamp: February 08, 2024, 10:03:37 pm
content: Quote from: JJ_023 on February 08, 2024, 03:26:39 pmA simulator is neither a development environment nor a debugger. It is a tool.Mathematical modelling is valuable in some ways, but has limitations.Simulation is valuable in some ways, but has limitations.Physical prototyoes are valuable in some ways, but have limitations.Engineering is about choosing the right tools so that one tools strengths outweigh another tools weaknesses.All are good. Repeat: all are bad.QuoteBreadboards have their limitations, some more than others (I particularly dislike the unnecessary problems people find with solderless breadboards). Nonetheless, they are valuable.Example: I recently simulated an HV capacitor multiplier. It all worked nicely in the simulator and enable me to spot and and remove a few problems. Nonetheless a quick partial prototype revealed I had forgotten to think about the electrolytic capacitor's leakage current. WhoopsQuoteNeither does getting one prototype to work guarantee that the next will work.Mathematical modelling is frequently based on the assumption of linearity, so that superposition can work. Without that the maths becomes intractible.Simulation can include non-linear effects, but often obscures "the big general picture"; it is too easy to see the trees but not the wood. Many simulations can help understand sensitivity factors.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 08, 2024, 11:14:30 pm
content: Quote from: RoGeorge on February 08, 2024, 07:06:36 pmI can definitely honor your request and will not thank you anymore.The only thing I can say about QSPICE is I have gotten literally zero spam emails from them. I think the download code that you are referring to is to validate the email. The actual download if I remember is just a link. Once I did that they have not once made contact with me.Also they never ask you to do that process again when you update the software.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 08, 2024, 11:18:22 pm
content: Quote from: twospoons on February 08, 2024, 09:22:01 pmThanks for the heads up. I never really heard of this particular simulator. I will have to check it out. Do you know what the price is for the full version?What is the node limit if you know off the top of your head?

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 08, 2024, 11:28:44 pm
content: Quote from: tggzzz on February 08, 2024, 10:03:37 pmI understand the argument that you are presenting and all of it makes sense. Different tools for different scenarios.I was wondering what type of bread boards have the least amount of limitations. Like everything else I assume there are better quality ones. The ones I use are generic $10 ones. I don't mind spending money on decent things. I have seen bread boards that are 10 times the price but I never purchased one because I never knew which ones were considered the better ones.

author: tggzzz
author_rank: Super Contributor
timestamp: February 08, 2024, 11:41:57 pm
content: Quote from: JJ_023 on February 08, 2024, 11:28:44 pmYou seem to be talking about solderless breadboards; there are many other types. For a range, seehttps://entertaininghacks.wordpress.com/2020/07/22/prototyping-circuits-easy-cheap-fast-reliable-techniques/Basically there are a whole range of techniques which can be mixed and matched as appropriate.How would you model this solderless breadboard prototype? Pay particular attention to the (missing) connection on the right(IIRC LTSpice has a neon model in its library.)

author: twospoons
author_rank: Frequent Contributor
timestamp: February 09, 2024, 12:37:11 am
content: Simetrix Demo Node limit is 140 nodes. Cant recall the price exactly and they dont list on the website, but its north of 1kUSD, depending on options.Demo version limits for simetrix:Quote@tggzzz Thats a nice demo of one of the primary gotcha's of solderless breadboard!

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 09, 2024, 02:47:10 am
content: Quote from: tggzzz on February 08, 2024, 11:41:57 pmI inferred that you were talking about solderless breadboard's. That is the reason why I asked if you had a particular product in mind.The link that you sent somebody sent me that in one of my previous posts ( it might have been you) I read that already and I am very familiar with it.When you ask me how I would model it, what exactly do you mean by that? In a simulator?As far as what I see on the breadboard.I believe that is an incandescent lightbulb.One of the connections is not connected directly.My guess is due to the inductance in the breadboard due to the metal clips a circuit is being completed.My question is what would happen if you moved over an additional two rows?

author: LinuxHata
author_rank: Frequent Contributor
timestamp: February 09, 2024, 06:05:14 am
content: It is very funny to read about "big support team behind the ltspice" when these Gentlemans can only offer 16 color EGA palette for plot line selection and you have no control over the colors/thickness/etc. And there are certain colors, like dark blue, which are very hard to read against the black background, and you have no control over it, since software assigns it on random, so you have to change it AFTER.

author: Ian.M
author_rank: Super Contributor
timestamp: February 09, 2024, 06:31:26 am
content: Menu:Tools->Color Preferencesopens a dialog that lets you set the RGB for each LTspice color. There's no color picker, just RGB sliders and numerics, but its certainty possible to tweak the blues and greens so dark blue and green are more visible against a black background.

author: LinuxHata
author_rank: Frequent Contributor
timestamp: February 09, 2024, 06:49:08 am
content: Still no control over colors - like, you can not apply rules, so say, current measurements will be always say, shades of red, voltages, shades of green and so on.I just downloaded QSPICE. They have a bit better control over that, but still, no pre-defined color assignment rules.By the way, while some improvements are definitely made in QSPICE, some things are even more complicated - for example, can't find how to add power source to the schematics

author: RoGeorge
author_rank: Super Contributor
timestamp: February 09, 2024, 07:11:02 am
content: That dark blue is almost invisible.Fortunatly, the default setting for LTspice are stored in a text file:...\User\AppData\Roaming\LTspiceXVII.inifor Windows, or in/home/$USER/.wine/drive_c/users/$USER/Application\ Data/LTspiceXVII.inifor Linux,and can be kept somewhere else as copy backup. Mine looks like this file posted here:https://www.eevblog.com/forum/eda/where-does-ltspice-keep-its-settings/msg4150582/#msg4150582and in practice the schematic and plots have these colors:Peltz oscillator LTspice printscreens are fromhttps://www.eevblog.com/forum/projects/simple-sinusoidal-oscillators/,with the colors from the above LTspice settings file.

author: magic
author_rank: Super Contributor
timestamp: February 09, 2024, 07:54:59 am
content: Quote from: tggzzz on February 08, 2024, 11:41:57 pmThis is an easy case because row to row capacitance can be measured and included in the simulation.It would be harder if the circuit were meaningfully affected by inductance or mutual inductance of jumper wires.Even harder - I'm not sure how to model random and randomly time-varying resistance, when that starts to matter

author: iMo
author_rank: Super Contributor
timestamp: February 09, 2024, 08:07:02 am
content: The row capacitance is aprox 3.5pF on those solderless breadboards, afaik..

author: Ian.M
author_rank: Super Contributor
timestamp: February 09, 2024, 09:00:47 am
content: Dave measured it. See:https://www.eevblog.com/forum/blog/eevblog-568-solderless-breadboard-capacitance/A quality breadboard may have significantly lower capacitance due to use of plastics with a lower dielectric constant, and better contact design minimising the side area and proximity to the wall between strips. Boss Industrial Mouldings Ltd used to quote 0.5pF between adjacent strips of theirBimboardrange.

author: RoGeorge
author_rank: Super Contributor
timestamp: February 09, 2024, 09:27:29 am
content: Quote from: magic on February 09, 2024, 07:54:59 am- For pseudo random, probably a file with predefined values, then a PWL (PieceWise Linear) source to read that file.- For time variable resistor, LTspice has a variable called 'time', which can be used inside newly defined functions or behavioral sources.Example of using the internal LTspice variabletimeinside a simulation (timevariable can be used in plots, too):Hilbert Transform simulation LTspice printscreen fromhttps://www.eevblog.com/forum/programming/extract-precise-amplitude-and-phase-from-a-frequency-sweep-(vna-from-dsoawg)/

author: tggzzz
author_rank: Super Contributor
timestamp: February 09, 2024, 09:32:37 am
content: Quote from: JJ_023 on February 09, 2024, 02:47:10 amGlad you found it helpfulYes, model it in a simulator. That question is designed to highlight the strengths and limitations of mathemetical modelling, simulations, and solderless breadboards.QuoteGood last questionThe neon bulb lights with the right hand wire in rows 1,2,3,4 but not 5 or further away. I will take a picture of that, for future referenceIt wouldn't work with an incandescant bulb since that would require too much current.What's happening is that there is capacitative coupling between the adjacent rows of the (unmodified) solderless breadboard. The internal parallel flat plates are acting as capacitors, and the 150kHz AC power supply is "passing through" that capacitance.Now capacitive coupling occurs everywhere, e.g. it is enlightening to use the standard mathematical models to calculate the capacitance of the earth-moon pair. Hence capacitive coupling can and does occur with other breadboard techniques, but can be arranged to be less "severe": firstly the wires have smaller area and are unlikely to be parallel, and secondly a well decoupled nearby ground plane has a tendency to "short circuit" the current (to use an informal handwaving explanation).The inductance problem (again present wih all construction techniques) is because when the current through a conductot changes (especially a ground/Vcc connection), a "back EMF" voltage opposes the change in current. That is a particular issue with digital circuits, but also with high speed or sensitive analogue applications. Keep wires short and loops small

author: tggzzz
author_rank: Super Contributor
timestamp: February 09, 2024, 09:36:27 am
content: Quote from: magic on February 09, 2024, 07:54:59 amYes on all countsThe point is, of course, that the mere existence of the capacitance has to be appreciated (a problem for beginners!) and its value estimated.As I have just noted, the question is designed to highlight the strengths and limitations of mathemetical modelling, simulations, and solderless breadboards.Hoperfully the modelling of the consequences of time-varying resistances can best be achieved by surrounding the existing model with a large round metal object - open at the top so that it can't be simplified by assiming it is a Faraday cage

author: Ian.M
author_rank: Super Contributor
timestamp: February 09, 2024, 09:52:30 am
content: LTspice also supports behavioral resistors, and has rand(x) and random(x) functions, which generate a new pseudorandom value as x crosses each integer value. rand() is unsmoothed (i.e. level step level step ...) but random() fits a curve between them. N.B. If x repeats exactly, so will the pseudorandom sequence.You can thus create a psuedorandom resistance simply by setting the value of a resistor to:Code:R={Rmin}+{Rmax-Rmin}*random(time/{tscale}+{seed})tscale is the time interval between psuedorandom samples, and seed is an integer to start the sequence at different offsets.Edit: I forgot the {} round seed. It seems to work without them but better to do it right.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 09, 2024, 03:14:10 pm
content: Quote from: LinuxHata on February 09, 2024, 06:49:08 amI am not sure if this is what you mean. But if you hit the "V" key it will bring up a voltage source. Then you have a command prompt to define the source.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 09, 2024, 03:19:01 pm
content: Quote from: Ian.M on February 09, 2024, 09:00:47 amAre the BIM boards still available? I did a quick search and could not find anyone selling them or a website for them.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 09, 2024, 03:32:05 pm
content: Quote from: tggzzz on February 09, 2024, 09:32:37 amI will be honest I personally would not know how to model this particular scenario in a simulator. However having read some of the previous posts I would probably do it with a capacitor in series with the bulb. Would that be the correct way?QuoteSo I was aware of inductance and capacitance problems with wiring and bread boards especially after reading some of the linked material in this post and previous posts.I wrongly assumed that it was inductance that was a problem but now that you elaborated what is happening it makes sense. I knew the metal clips would be involved somehow and it makes sense that there would be capacitance based on the air gap which in this case would be the dielectric.As embarrassing as it is I am not familiar with the neon bulb. I do not know the current requirements to light one versus incandescent that is why I stated incandescent.My follow-up question is will this work with an LED since its current requirements are very small? My guess is it would.I also assume you used some sort of switch mode power supply due to the 150 kHz mentioned.If you put a decoupling capacitor on row 2 that should make the light go out. Is this correct?

author: tggzzz
author_rank: Super Contributor
timestamp: February 09, 2024, 04:35:52 pm
content: Quote from: JJ_023 on February 09, 2024, 03:32:05 pmThe key point is that the circuit works (or fails!) because of "unexpected and invisible" parasitic components. Minimising those is part of sound circuit design; almost always the intention is that the circuit's operation is determined by well-defined components. No surprise there!There are, in general, many parasitic "components" most of which are probably unimportant. In this circuit the important parasitic component that allows the effect to be visible is a capacitance in series with the neon and voltage source. Hence the effect could be demonstrated by a model containing the AC voltage source, capacitor, neon, plus resistor representing the internal source resistance of the voltage source.It would be non-trivial to choose the capacitance value, and given the very strange piece of test equipment I used as a voltage source, determining appropriate values for the voltage amplitude and resistance wouldn't be trivial.QuoteHaving a good mental model of what's present and what's happening leads to such understanding. Having a knowledge of theoretical models and behaviour is a pre-requisite for making sense when an implementation doesn't behave as expected. Simulation can sometimes be used to confirm the cause of observed behaviour.QuoteDon't be embarassed; neon bulbs are largely obsolete. The nearest component used in modern equipment is a gas discharge tube used to protect against high voltage transients on PSU inputs.They were used for strange things; before I sold it I had a Fluke DVM that used a neon as the reference voltage. Since it wasn't very stable, it had a front-panel control that enabled the displayed value to be tweaked until it showed 1.019V, the same as a (stable) Weston standard cell. You can also implement digital logic with them, but I wouldn't recommend it!Neons require 60-120V to illuminate, but the current is 10s of microamps. Thus a LED might illuminate, but not brightly.QuoteThe voltage source was just something I had to hand, a strange device used for testing bulbs, a TIS1040. It is more an oscillator than an SMPS.

author: tggzzz
author_rank: Super Contributor
timestamp: February 09, 2024, 04:52:04 pm
content: Quote from: tggzzz on February 09, 2024, 04:35:52 pmConfirmed. A modern high-efficiency LED illuminates dimly, on the adjacent strip only. Older LEDs don't illuminate.

author: Ian.M
author_rank: Super Contributor
timestamp: February 09, 2024, 04:56:22 pm
content: Quote from: JJ_023 on February 09, 2024, 03:19:01 pmUnfortunately not. The company went under back in 2008, and IIRC ceased breadboard production well before that date.

author: MarkT
author_rank: Frequent Contributor
timestamp: February 09, 2024, 09:02:19 pm
content: And I suspect that 0.5pF number was erroneous anyway given the data from all the other breadboard!

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 10, 2024, 12:41:22 am
content: Quote from: tggzzz on February 09, 2024, 04:35:52 pmThank you for such an elaborate response.So I googled your power supply and watched a video on it. It's basically used for testing all sorts of lightbulbs. It also has a continuity feature. How does it work I didn't see a ground clip? It talks about holding one end in hand so I assume the person completes the circuit?

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 10, 2024, 12:47:58 am
content: Quote from: tggzzz on February 09, 2024, 04:52:04 pmYou never answered my question. Would a decoupling capacitor cause the neon light to go out?

author: tggzzz
author_rank: Super Contributor
timestamp: February 10, 2024, 12:56:52 am
content: Quote from: JJ_023 on February 10, 2024, 12:41:22 amYou're welcome. It is a pleasure to someone that asks questions and thinks about the responsesThe TIS1040 is indeed.... a weird curiosity. It appears to rely on several "abnormal" effects that won't be seen by the lamps in normal operation. It seems to be a simple very quick and dirty tool that electricians can use in the field as a go-no-go tester. However, its reliability is unclear to me; certainly it doesn't always give the results I would hope and expect. I've only got it since it came as part of a job-lot of useful stuff!.

author: tggzzz
author_rank: Super Contributor
timestamp: February 10, 2024, 01:00:12 am
content: Quote from: JJ_023 on February 10, 2024, 12:47:58 amI would expect so. But the capacitor would have to be between the appropriate nodes, and there are several parasitic elements around there, so perhaps not.It might well be an example where a theoretical model is so simple it does not adequately represent the physical circuit.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 10, 2024, 01:40:35 am
content: Quote from: tggzzz on February 10, 2024, 12:56:52 amI was hoping you would tell me how it works? lol

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 10, 2024, 01:44:40 am
content: Quote from: tggzzz on February 10, 2024, 01:00:12 amSo I understand your response. My interpretation of your response was that it would be very difficult to model in a simulator.I guess one would have to take proper measurements of the breadboard to understand the capacitance and Inductance associated with it to then be able to model that particular circuit. Is that a correct assumption?If my assumption is correct then you might as well just build the circuit and figure out the specifics in a real-world model which you are trying to develop anyway.

author: RoGeorge
author_rank: Super Contributor
timestamp: February 10, 2024, 08:06:05 am
content: The good part about breadboard is that the parasitic R and L and C values are usually small enough, such that most of the time those unwanted effects can be neglected.When it comes to high impedance circuits (megaohm range or more), or to high frequency (MHz range or more), then a 0.5pF between 2 nearby columns in a breadboard might influence the circuit too much, so a breadbord construction won't work very well (or won't work at all).The good side is that there are plenty of other circuits left to try on a breadboard: DC, audio, microcontrollers, learning the basics of electronics, etc.About breadboard builds, there is a much bigger danger than parasitic capacitance: Circuits on a breadboard have the tendency to become permanent. After a while, one might end up with a just bunch of breadboards stuffed with components, and no nicely finished projects.If all your breadboards are full, that's the sign, don't buy more breadboards!In the same category of pitfalls, while simulation is a very useful and powerful tool, it may sink a lot of time. One might easily spend hours and hours fiddling with a simulation (which might not even correspond good enough with the reality), instead of just soldering the darn thing on a copper clad. After all, the best physics simulator ever is the Universe itself.At the end of the day, might be more rewarding to have a soldered circuit thatdoesn'twork (because that still feels like you've built something), than to have a simulated circuit that works, yet it was not put in practice.My point is, while breadboards and simulators might come very handy, there is a tendency to overuse/abuse them. That will waste a lot of time, and at the end of the day you still won't have the wanted circuit for real, in a nice enclosure.Simulate only small portions of a circuit, those portions about which there is doubt, then also breadboard/prototype that small part of the circuit, to double check the simulation results. Then make it for real, don't skip this last part.

author: tggzzz
author_rank: Super Contributor
timestamp: February 10, 2024, 08:54:10 am
content: Quote from: JJ_023 on February 10, 2024, 01:44:40 amA simulation will show you the response of whatever you model, of courseThe more complex the model, the more realistic the results (in general!). One thing I sometimes do is add "extra" components to a circuit model, and use a simulator to see how much they change the behaviour. Hopefully realistic values don't change its behaviour too much.It is an example of the "all models are false, but some are useful" aphorism. There are many such models, e.g. the concept of "ground" or "earth". Knowing when a model is useful and when it fails requires experience, skill, and good judgement. Sometimes knowing where they fail allows components to be used to good effect in circuits with surprisingly good performance. There are some examples of that in TAoE and TAoE x-ChaptersIf you think about it, simplified models are everywhereand the abstractions allow analysis of circuits. When modelling a computer program, you don't worry about logic gates. When modelling a digital computer's logic gates, you don't worry about voltage levels. When modelling voltage levels, you don't worry about electrons. When modelling electrons, you don't worry about electromagnetic fields. But if you violate the applicability of the lower level models, the higher level operation won't be what you expect. Violate "signal integrity" and the logic will "misbehave". And then there's planar microwave circuits, where shaped conductors are filters and power is transmitted by EM fields guided by the currents produced by the EM fields. Or undersea power grid connections where DC is used since it is less lossy than AC.Personally I prefer to recommend to beginners that they adopt (construction) techniques that show fewer "strange" problems and are more likely to be succesful.

author: tggzzz
author_rank: Super Contributor
timestamp: February 10, 2024, 09:15:11 am
content: Quote from: RoGeorge on February 10, 2024, 08:06:05 amExcept where those parasitic values aren't too small and do affect the operation. Every digital logic circuit is an RF circuit. Workstations started "doing arithmetic in the FM band" back in the 80s. Modern MCUs do the same in the UHF band, and the stunning advances in ADCs and DACs mean they are computing in at microwave frequencies.Parasitic capacitance isn't usually a problem for MCUs and logic gates, but parasitic resistance can be andparasitic inductanceisa killer. The latter is true even with ICs on PCBs; some TTL/CMOS buffers in the late 80s gained a very bad reputation because of that. Nowadays big complex logic devices come with IBIS models of the package. (IBIS contains RLC models of the bits between the silicon and the PCB).Somewhere I've got a picture of a BGA IC with many many wires that could be connected to a breadboard. Nobody in their right minds does thatQuoteIt isn't so much a problem with solderless breadboards. That problem is cured when you sneeze or drop the circuit or bruch against wires when storing/retrieving the circuit.It is more a problem with manhattan prototyping, but all you have to do is pull another piece of double-sided copperclad board from the cupboard, and polish off the tarnishQuoteYes and yes. But it is even better to have avoided easily avoidable problems, and to have a working circuit.QuoteYes and yes. "All models are false, but some are useful"Good taste is required to know which tool to use/avoid, and to get successful outcomes.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 11, 2024, 07:00:23 pm
content: Quote from: RoGeorge on February 10, 2024, 08:06:05 amAll my bread boards are cleaned after every experiment.One of the things I found helpful about simulators is when doing node analysis or KVL or KCL I can make up some weird circuits with resistors and then by hand calculate what is expected and then use the simulator to check my results. I found this type of experimentation on a Simulator a lot easier then a breadboard.I am pretty decent at soldering and have a decent soldering iron and most importantly I feel comfortable doing it.What is your preferred methodology when playing around with components and building nonpermanent test circuits? (besides breadboard)

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 11, 2024, 07:10:31 pm
content: Quote from: tggzzz on February 10, 2024, 08:54:10 amI own a copy of the art of electronics. I think it is a great reference book but a terrible book for learning electronics. I found much better books for understanding the fundamentals. That is just my opinion however. I think down the road as my knowledge increases then the art of electronics will start to be more appreciated.I have read numerous posts by you in regards to breadboards. I also highly value your opinion on a lot of things that you shared with me in response to my current and past posts. I understand all the negatives that you describe about Breadboards but as a beginner I still find them useful on occasion. I think I will always find them useful for basic stuff. The value that I got from your posts was to be aware of their pitfalls and limitations and to keep them in mind when dealing with breadboards. I also realized that there are Bread boards that are better than others, which my intuition told me would be the case but now at least I know in which direction to look for better breadboards.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 11, 2024, 07:17:26 pm
content: Quote from: tggzzz on February 10, 2024, 09:15:11 amCould you please elaborate on this statement. Especially on the parasitic inductance. I understand how parasitic inductance at higher frequencies affects capacitors but I am looking to learn more.

author: tggzzz
author_rank: Super Contributor
timestamp: February 11, 2024, 10:32:19 pm
content: Quote from: JJ_023 on February 11, 2024, 07:10:31 pmI think that is exactly right.TAoE is good for someone that already understands the fundamentals and has built some basic circuits - and now wants to expand their repertoire of techniques. In other words, someone who had completed a degree course (or equivalent) and now wants to put that knowledge into practice in industrial settings.QuoteThat's fine. I always say pick and choose the appropriate combination of techniques for the job at hand. All techniques have their downsides.

author: vk6zgo
author_rank: Super Contributor
timestamp: February 12, 2024, 01:05:05 am
content: Quote from: LinuxHata on February 07, 2024, 04:34:07 amAs a nasty old man, I really dislike LTSpice.It was not always so, but after downloading it & trying to simulate quite basic circuitry, I found it incredibly non-intuitive.Another "niggle" is its habit of showing ac sources using a classic DC generator symbol.I decided I don't have enough years of life left to learn how to use something I would probably use once or twice, so didn't bother anymore.Meanwhile, I kept seeing a parade of Noobs in the Beginner's section asking "Why doesn't this work in real life when it does on LTSpice?"A classic was the person who thought they were making a "Tuned Radio Frequency" radio receiver.To this end, they used a standard Op Amp circuit with negative feedback from output to input, then put LC tuned circuits at input & output.LT Spice assumed that the two LC networks were perfectly identical & tuned in step over the required range, so all would be well.In the real world, that was not the case, so there was enough phase shift to turn the NFB to positive feedback, creating an oscillator.Similar questions popped up regularly for some years, with in some cases, the "Noobs" being so "wedded to" LT Spice that they would argue with those trying to point out its limitations.

author: tatel
author_rank: Frequent Contributor
timestamp: February 12, 2024, 03:10:02 am
content: Quote from: JJ_023 on February 11, 2024, 07:00:23 pmI'm doing just that right now. It's my first contact with a simulator. Since I'm on Linux the obvious option for me is ngspice. More so because I'm planning to use Kicad in the future.I see you don't list ngspice among your options, yet it's a simulator that looks as having good user base and developing at good pace.https://ngspice.sourceforge.io/news.htmlI would like to know why you don't consider using it

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 12, 2024, 04:20:31 am
content: Quote from: tatel on February 12, 2024, 03:10:02 amI use KiCAD. I've never really heard of NGSPICE. I will check it out. Thank you.

author: RoGeorge
author_rank: Super Contributor
timestamp: February 12, 2024, 12:31:27 pm
content: Quote from: vk6zgo on February 12, 2024, 01:05:05 am- squared shaped symbol for resistor is in  directory, named 'EuropeanResistor'- triac symbol is in  directory, named 'TRIAC', comes with the default install- components limits are included in the model, not in LTspice itself. So if we chose, say a model of transistor that simulates the reversed breakdown voltages, LTspice will consider those limits, too. This is an example of a 2N3904 with breakdown:The upper plot is without breakdown voltages included. The second plot is for the same type of transistor, just that the model now includes breakdown voltages. The model 2N3904 is included in LTspice by default, but BD3904_BD is not. Second one is from Bordodynov's library.First thing after installing LTspice would be to add the Bordodynov's library, seehttps://ltwiki.org/?title=Components_Library_and_Circuits.That library includes many additional models, components and symbols. Apart from models and symbols, Bordodynov's library has many interesting circuits and examples, too.Anyway, the main idea with simulators, in general, is to see how a schematic works, not how it breaks. Most models won't include breakdown condition, unless the breakdown is essential for normal functioning (like in a Zener diode).- the other symbol for AC sources is just like the other "missing" symbols, in the  category, named 'signal'- in LTspice, the values are exact, so 2 LC with the same values for L and C will be identical. Same, 2 transistors of the same model will be perfectly identical. When needed, deviations can be specified manually different ways.Not trying to convince anybody to use something they don't like. Writing all these when I see such posts (deterring from using LTspice or other simulators), because no longer than a few decades ago I've read an article from Bob Pease, where he was ranting against simulators. That rant article, plus the quote "My favorite programming language is soldering", made me to avoid/disregard simulators and programming.Both of those ideas turned out to be a damaging advice for me. I was a kiddo back then, and took that rant as a must-follow life-guideline. Took me years to realize it's the contrary: both simulation and programming are not something to stay away from. The hardest prison to escape is the cage of our own mind.As anything else, simulation has its limitations, traps and disadvantages. But overall, simulation can be very helpful. Of course, the ultimate test is to put the ideas in practice and build the physical circuit, nothing can beat the joy of doing that.

author: watchmaker
author_rank: Unknown
timestamp: February 12, 2024, 12:57:31 pm
content: Quote from: JJ_023 on February 11, 2024, 07:10:31 pmArt of Electronics was one of the first books I purchased. I agree with you entirely, it is a great reference but it is not a path to LEARNING. Another better book for those of us starting out is Practical Electronics for Inventors by Sherz et al:https://www.amazon.com/gp/product/1259587541/I also echo the cautions and alternatives to breadboards. But they provide a beginner with an easy way to learn the methods of DC ckt analysis which is such a critical foundation. I understand that as I progress, their limitations and artifacts will diminish their utiity.OTOH, most of our first ones are cheap (I ordered one from Assembly Specialists who make the 3m) and the cheap ones make great storage for op amps, regulators, and such.

author: tggzzz
author_rank: Super Contributor
timestamp: February 12, 2024, 01:01:48 pm
content: Quote from: RoGeorge on February 12, 2024, 12:31:27 pmExactly.Use one tool's advantages where another tool's disadvantages are too limiting. That's a principal engineering skill!Nobody in this thread has mentioned other types of analogue simulators, e.g. harmonic balance simulators and electromagnetic field simulators. Both are necessary for the phenomena that SPICE simulatorsdon'taddress.(And perhaps a slightly different URL?https://ltwiki.org/index.php?title=Components_Library_and_Circuits)

author: tggzzz
author_rank: Super Contributor
timestamp: February 12, 2024, 01:04:20 pm
content: Quote from: watchmaker on February 12, 2024, 12:57:31 pmOooh! I hadn't thought of thatMight be slightly better (w.r.t. ESD) if each row is connected to all the other rows.

author: Ian.M
author_rank: Super Contributor
timestamp: February 12, 2024, 01:12:22 pm
content: LTspice requires you to use your brain because it doesn't have all the UI 'bells and whistles' and in circuit animated displays and alerts some other simulators offer. This is generally good for both you and your design though it does make the initial learning curve a bit steeper.e.g. you should have a pretty good idea which parts of your circuit are likely to be pushing their dissipation limits, so rather than looking at the schematic to see which parts are e.g. flashing red in a simulator that alerts you to such things, you Alt-click a part to see its instantaneous power (dissipation) in the waveform viewer, then for pulsed power, zoom it to an appropriate timescale (e.g. one of the pulse lines on its datasheet SOA or thermal response charts), autorange the Y axis if any part of the trace is off-screen, then Ctrl-click the trace legend to see the average power and integral. If you then need repeatable numbers for a report or to validate changes you make, set up a .measure statement to calculate the integral of the instantaneous power between two time limits.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 12, 2024, 02:28:26 pm
content: Quote from: watchmaker on February 12, 2024, 12:57:31 pmThank you for the book recommendation I will check it out.

author: JJ_023
author_rank: Frequent Contributor
timestamp: February 12, 2024, 02:32:35 pm
content: Quote from: Ian.M on February 12, 2024, 01:12:22 pmThank you for the tips. I will have to play around with them as I am unfamiliar with most of what you wrote.

author: metebalci
author_rank: Frequent Contributor
timestamp: February 13, 2024, 08:28:37 am
content: TI also offers PSpice for TI, and particularly for new ICs I do not always see TINA-TI models. I wonder if they plan to discontinue TINA-TI or plan to support it only for a limited set of products. I know it is easy to add a PSpice model to TINA but still I find it strange some products do not have a ready-to-use model out of the box for TINA-TI.

author: tipa
author_rank: Newbie
timestamp: March 17, 2024, 10:49:50 am
content: Hello, watchmaker! I am a Multisim fanatic. Therefore, I recommend this program. But not the online version, but the stationary one. I have the 'cracked' version 14.2.0. It's been working fine for 4 years now. Full of all sorts of 'twists' and sliders. Good animation, in interactive mode everything can be adjusted on the fly

author: Zero999
author_rank: Super Contributor
timestamp: March 18, 2024, 08:55:26 am
content: Quote from: vk6zgo on February 12, 2024, 01:05:05 amThat pretty much applies to all simulation software to some degree, not just LTSpice. Except the part about the GUI, which a good number of people find unintuitive, but it's not something which I personally struggled with.This may sound a little elitist, but I often think simulatoers are too easy to use, rather than the reverse. If you had to enter the schematic in the form of a net list, then it would force beginners to learn more about how it works and that it's just performing calculations, rather than magic.

author: CircuitAnalysis
author_rank: Newbie
timestamp: May 10, 2024, 06:28:09 pm
content: I got tired of the interfaces in PSPICE, SIMPLIS, LTSPICE, PSIM... so I write my own I call Bolt, which is very new and uses the open source NGSPICE simulator. It is designed to be a nice looking, light weight frontend the complements the SPICE code instead of trying to fully abstract it. It is very early and will have a lot more features added, but if you want to give it a try you can go to:https://www.circuitanalysis.com/You have to make an account to download it, but it is free for both Mac and Windows and I plan to add Linux at some point. I setup a discord in case anyone want's to chat in real-time to ask questions or give feedback.I also have made and will make more video tutorials on how to simulate different types of circuits in this YouTube playlist:https://www.youtube.com/playlist?list=PLPJa0dSdlB4XFScl976TVHVoVZS2a58-aBesides Bolt, for free options I would recommend checking out:-LTSPICE-QSPICE (written by the guy who wrote LTSPICE)-Micro-Cap (written buy a guy who retired and decided to make it free now bit it won't get any more updates)Note that all SPICE simulators are based on Berkley-SPICE, so they all basically have a graphical part where you draw your circuit that it then transforms into a netlist and runs through the SPICE solver to create a data file, which is then loaded into a waveform viewer.

author: watchmaker
author_rank: Unknown
timestamp: October 22, 2024, 12:20:42 pm
content: I have gotten used to MultiSim 14.3 but after trying the Tina 14 demo I paid for the student version.My use is for following EE courses thru online or text. I want programs that allow me to input the ckts from these sources with the minimum of fuss. While I do not see getting into PCB design, it looks like TINA 14 accommodates this. Should I get that far, I know there are PCB vendors who have easy to use tools.It is more intuitive to me, offers many examples and is fast on my laptop. The simulator display requires more attention than multisim (I like being able to use the right axis in MS). I also bought the student examples package which includes problems related to EE 101 and maybe a little beyond.Have tried MicroCap, PSpice, LTSpice and Kicad. They are either too limited, cause me grief in connecting pins or I cannot change the schematic texts for things like footprint and such.Both Multisim and Tina 14 make it easier. Both are very mouse oriented as opposed to some other programs that are keyboard oriented.I had tried Tina 9 and found it useless which is when I settled on MS. When you look at the Tina 14 site it looks sketchy; but it is just old school like the GUI theme Tina uses. When I looked at their other products (edison/newton) I was concerned that the files for those are all from 2009 or so. But this was not true for the Tina14 Demo files, all 2022/2023. SO I took the plunge.FWIW, I only use non cloud based software. I want to OWN it and know it will not disappear or pay subscriptions.