Mike Engelhardt's new SPICE simulator QSPICE is out

[Jope]

Mike Engelhardt's post on LinkedIn talking about release

QSPICE website

EDIT:
The redirect from www.qspice.com doesn't seem to work anymore.
Direct URL: https://www.qorvo.com/design-hub/design-tools/interactive/qspice

[firewalker]

I hate whet they want personal infos in order to download. Google in;t happy.

[nctnico]

No Linux version??

[iMo]

Until Qspice can read the existing .asc files and libraries I doubt it comes to a significant move from LTspice to Qspice..

[firewalker]

No Linux version??

It might be WINE compatible. Like LTspice.

Alexander.

[nctnico]

No Linux version??

It might be WINE compatible. Like LTspice.

Unfortunately most software isn't Wine compatible. I have given up on trying to use Windows software on Wine a long time ago.

[alm]

Unfortunately most software isn't Wine compatible. I have given up on trying to use Windows software on Wine a long time ago.

Wine has improved a lot over the past decade. I guess whether it runs "most" software depends on your sample. But LTspice has been running well for a long time already.

[SiliconWizard]

Unfortunately most software isn't Wine compatible. I have given up on trying to use Windows software on Wine a long time ago.

Wine has improved a lot over the past decade. I guess whether it runs "most" software depends on your sample. But LTspice has been running well for a long time already.

It does. The only thing that does not is updating LTSpice itself from within the app. But updating components does work.

[firewalker]

Unfortunately most software isn't Wine compatible. I have given up on trying to use Windows software on Wine a long time ago.

LTSpice is purposefully (used to at least) build to be compatible with WINE.

Alexander.

[nctnico]

Unfortunately most software isn't Wine compatible. I have given up on trying to use Windows software on Wine a long time ago.

Wine has improved a lot over the past decade. I guess whether it runs "most" software depends on your sample. But LTspice has been running well for a long time already.

People have been saying that for decades  But realistically, QSpice is Windows 10/11 only so likely needs the latest .Net and Windows APIs to work. How far along it Wine with that? And even then, chances are high QSpice (or any other program) use a sequence of API calls that work differently that expected. If you look at the supported software list from Wine you'll see Wine needs to be tweaked/fixed for most software to work OR the software must be made to be compatible with Wine (which seems to be the case for LTSpice but LTSpice doesn't have a particulary demanding GUI to begin with).

In the end it makes much more sense to write new software cross-platform from the start rather than relying on emulation nowadays.

[Warhawk]

I am just about to install it. What upsets me a bit is the online installer. Does anyone know if there is an offline installer?

[Zero999]

I have no intention of installing it.

What does it offer, which LTSpice does not?

[magic]

Supposedly better performance with lots of digital logic and higher quality graphics or something like that.

I wonder if there are any plans to make it run on different CPUs like perhaps ARM - currently "Intel" is spelled out quite explicitly in the description.
Probably none like with LTspice

[iMo]

FYI - the Qspice forum..

https://forum.qorvo.com/c/qspice/9

[Warhawk]

I have no intention of installing it.

What does it offer, which LTSpice does not?

LTspice license excludes my employer (thus me) from using it. pSpice is too bloated for most of my simulations.

[Zero999]

I have no intention of installing it.

What does it offer, which LTSpice does not?

LTspice license excludes my employer (thus me) from using it. pSpice is too bloated for most of my simulations.

Out of curiosity, what part of the licence excludes your employer from using it? I don't recall it prohibiting commercial use.

[Warhawk]

I have no intention of installing it.

What does it offer, which LTSpice does not?

LTspice license excludes my employer (thus me) from using it. pSpice is too bloated for most of my simulations.

Out of curiosity, what part of the licence excludes your employer from using it? I don't recall it prohibiting commercial use.

"This program is specifically not licensed for use by semiconductor manufacturers in the design, promotion, demonstration or sale of their products." 

[exe]

Their website is down for the second day in a row: "Site Temporarily Down for Maintenance We apologize for the inconvenience. Please try again in a short while.".

Too bad, I wanted to try a new UI .

[Jope]

Their website is down for the second day in a row: "Site Temporarily Down for Maintenance We apologize for the inconvenience. Please try again in a short while.".

The website is up again, but it seems the Qspice stuff is not there.
The former download link was this: https://p.qorvo.com/get-qspice

[Gerhard_dk4xp]

works for me.

Gerhard

[SiliconWizard]

Just tried installing it under Wine, but the installer fails immediately with the attached error message. And yes, I have tried both setting Wine as Windows 10 and Windows 11, and yes, in 64-bit.
I guess the installer's method of identifying the OS recognizes it as not being Windows for some reason. So, it *may* work under Wine if the installer allowed it. Who knows.

If the author is interested in testing QSPICE under Wine, I'll happily do that once the installer is updated to allow it.

[iMo]

MikeE in the forum:

I gave up on WINE for QSPICE when I saw it converted DirectX12 calls to GDI. The problem is that that will be too slow and have pixelated graphics like the 1970s Pong game. I don’t see a path to getting QSPICE to a viable point on WINE. I’ll revisit it when WINE implements with DirectX12 API.

https://forum.qorvo.com/t/qspice-under-wine-in-linux/14598/5

[Veteran68]

MikeE in the forum:

I gave up on WINE for QSPICE when I saw it converted DirectX12 calls to GDI. The problem is that that will be too slow and have pixelated graphics like the 1970s Pong game. I don’t see a path to getting QSPICE to a viable point on WINE. I’ll revisit it when WINE implements with DirectX12 API.

https://forum.qorvo.com/t/qspice-under-wine-in-linux/14598/5

Interesting take, I wonder how long he's had it under development. I've not looked at WINE in awhile, but there are commercial games that can run under WINE. By comparison to most games, circuit simulation graphics would be considered primitive. Then I just did a quick Google, and as of WINE 4.0 (Dec 2022?), it has support for DX12 through the Vulcan library.

https://www.epersianfood.com/wine-4-0-is-here-vulkan-directx-12-game-controllers-sweet/

[SiliconWizard]

MikeE in the forum:

I gave up on WINE for QSPICE when I saw it converted DirectX12 calls to GDI. The problem is that that will be too slow and have pixelated graphics like the 1970s Pong game. I don’t see a path to getting QSPICE to a viable point on WINE. I’ll revisit it when WINE implements with DirectX12 API.

https://forum.qorvo.com/t/qspice-under-wine-in-linux/14598/5

I see, thanks.

I personally don't see a point in requiring DX12 for a Spice simulator though to begin with. It's absolute overkill. Oh well.

[ataradov]

"This program is specifically not licensed for use by semiconductor manufacturers in the design, promotion, demonstration or sale of their products." 

Yep, banned at my job too. It is very annoying, but for my limited needs random online simulators do the job.

[ledtester]

If you like to hear Kiss Analog talk, here's his take on Qspice:

LTspice is dead but QSPICE is born - A Great New FREE Circuit Simulation Software
https://youtu.be/u3xkLTgoQec

Note: it is 43 minutes long (only 22 minutes if you watch it at 2x speed).

I learned a few things about Mike Englehardt and the history of LTspice. I also learned that if you've only designed DC/DC converters don't call yourself a power supply designer (according to Kiss Analog).

[Veteran68]

If you like to hear Kiss Analog talk

Ha, that's funny. Poor Eddie, he's a knowledgeable guy no doubt, but but he speaks like the world's worst introvert had a gun put to his head and told he has one chance to deliver a speech to 1M people to save his life. As long as he's been on YouTube you'd think he be a little smoother by now. He's so awkward, it's easy to think he's clueless. But obviously given his work experience and accomplishments he's a smart guy, especially about power supplies.

[iMo]

"This program is specifically not licensed for use by semiconductor manufacturers in the design, promotion, demonstration or sale of their products." 

Yep, banned at my job too. It is very annoying, but for my limited needs random online simulators do the job.

The license does not prohibit to use it by an employee of a semiconductor manufacturer at his home

[Warhawk]

If you like to hear Kiss Analog talk

Ha, that's funny. Poor Eddie, he's a knowledgeable guy no doubt, but but he speaks like the world's worst introvert had a gun put to his head and told he has one chance to deliver a speech to 1M people to save his life. As long as he's been on YouTube you'd think he be a little smoother by now. He's so awkward, it's easy to think he's clueless. But obviously given his work experience and accomplishments he's a smart guy, especially about power supplies.

I was thinking about how to describe my feelings after watching the linked video. You described it perfectly.

[nctnico]

If you like to hear Kiss Analog talk

Ha, that's funny. Poor Eddie, he's a knowledgeable guy no doubt, but but he speaks like the world's worst introvert had a gun put to his head and told he has one chance to deliver a speech to 1M people to save his life. As long as he's been on YouTube you'd think he be a little smoother by now. He's so awkward, it's easy to think he's clueless.

He is doing videos a whole lot better than I would, so I'm not complaining!

[Veteran68]

If you like to hear Kiss Analog talk

Ha, that's funny. Poor Eddie, he's a knowledgeable guy no doubt, but but he speaks like the world's worst introvert had a gun put to his head and told he has one chance to deliver a speech to 1M people to save his life. As long as he's been on YouTube you'd think he be a little smoother by now. He's so awkward, it's easy to think he's clueless.

He is doing videos a whole lot better than I would, so I'm not complaining!

His production quality has certainly increased and he does cover some good content. I've been a subscriber for quite awhile and appreciate his work. But he can still be exhausting to listen to. He just comes across as so uncomfortable on camera.

[mawyatt]

Had the pleasure of meeting Dr Larry Nagle (his PhD dissertation at Berkley was SPICE) at the ISSCC awhile back, a colleague worked with Larry at Bell Labs and introduced us. Larry was honored on the cover of IEEE Circuits and Systems magazine that year, and he is the foundation behind all SPICE based simulators.

Recall the Berkley SPICE as it was called back then, was licensed for $25 to anyone, so many licenses were issued. With all these SPICE licenses (was in FORTRAN) around folks began to try and port to the early PC recently introduced by IBM. Vaguely remember Microsim (PSpice) was founded to develop hardware with multiple processors (multiple intel 8088) to speed up SPICE, so a specific Spice hardware engine. This failed as did many other folks attempts at utilizing multiple processors and they then focused on their version of SPICE which became the widely known PSpice. The issue with multiple processors or selective simulations of various circuit aspects was how to intelligently divide up the computational workload on various simulation circuits and how to link the results, remember a company that showed a significant improvement in simulation speed by simulation of DRAM, but memory was relatively easy to divide as it's just same circuit (memory cell) replication over and over.

Also remember another SPICE flavor where they advertised a circuit that compared simulation times with other popular SPICE based simulators, we caught them an alerted others as they had changed the convergence criteria RELTOL, ABSTOL and some other parameters to allow quicker less precise convergence.

Dr Ken Kundert at Cadence created Spectra which was an extension of SPICE for RF, ironically Ken's PhD is also from Berkley!! Ken's creation Spectra and prior work really extended SPICE not only for RF use but in general. Remember the "look ahead algorithm" in time domain simulations was significantly improved and "found" details that typical SPICE based simulators would step over and miss. Also included some of the things we had prior developed before Spectra for simulation of noise effects in the time domain, the speed up of simulations of high "Q" oscillators and so on.

Anyway, looking forward to having some time to play around with QSpice, altho wish it was available for Macs!! Our only "serious" computer is a loaded up Mac Pro (Can type), and not a fan of Windows.

BTW don't think the video is all that bad, yes a little hard to follow, but Eddie has a brew alongside. If the viewer follows Eddie and has a couple brews, then it's much easier to follow  

Best,

[Smokey]

How did I not hear about this?  Exciting.  Installing now.... 

My big question is.... how is the model library support doing?  My biggest problem with LTSpice was 3rd party component models, or lack thereof.  Yes, I had the mega-library of parts someone made, but it was still missing common parts and the mechanism to get it installed where it gets overwritten when you upgrade was a huge pain.  I get it.  It's LT's program, so why make it easy to simulate other companies parts.. But that problem should be gone now!

A spice sim with a huge library, or at least an easy library sharing mechanism will be so much more useful. 

[Warhawk]

How did I not hear about this?  Exciting.  Installing now.... 

My big question is.... how is the model library support doing?  My biggest problem with LTSpice was 3rd party component models, or lack thereof.  Yes, I had the mega-library of parts someone made, but it was still missing common parts and the mechanism to get it installed where it gets overwritten when you upgrade was a huge pain.  I get it.  It's LT's program, so why make it easy to simulate other companies parts.. But that problem should be gone now!

A spice sim with a huge library, or at least an easy library sharing mechanism will be so much more useful.

Mike E. mentioned that they put a lot of effort to have QSPICE compatible with standard SPICE libraries. I am going to make the ultimate test. Downloading TL431 from TI and trying it 

[Smokey]

How did I not hear about this?  Exciting.  Installing now.... 

My big question is.... how is the model library support doing?  My biggest problem with LTSpice was 3rd party component models, or lack thereof.  Yes, I had the mega-library of parts someone made, but it was still missing common parts and the mechanism to get it installed where it gets overwritten when you upgrade was a huge pain.  I get it.  It's LT's program, so why make it easy to simulate other companies parts.. But that problem should be gone now!

A spice sim with a huge library, or at least an easy library sharing mechanism will be so much more useful.

Mike E. mentioned that they put a lot of effort to have QSPICE compatible with standard SPICE libraries. I am going to make the ultimate test. Downloading TL431 from TI and trying it 

Got everything up and running (Build Aug 13).  And it looks like out-of-the-box the included libraries has support for..... only Qorvo JFETs, SiC Fets, and SiC Schottkys....   That's it.  It has generic behavioral stuff, but no other specific parts.

Yes, I understand that I can go find the spice model text definitions and paste them in.  They have a video demoing that here:

Code: [Select]

https://www.youtube.com/watch?v=WGJkZSDY9iA
But I really don't want to make symbols for everything with a sub-circuit... I wonder what the roadmap is for the default library...
I would think this would be something that could be hosted on github. Contribute with pull requests.  Merge libraries.  One community library.

[Warhawk]

Well, I do not expect libraries for everything. That would be barely maintainable. For basic components such as diodes, mosfets, BJTs you typically just take the generic breakout model, change the value (e.g. 1N4148W). Then, you place a directive somewhere in your diagram

Code: [Select]

.MODEL 1N4148W D  ( IS=10.4n RS=51.5m BV=75.0 IBV=1.00u
+ CJO=2.00p  M=0.333 N=2.07 TT=5.76n )
This way it works in pSpice (@PSpice: .model. .....) and LTspice. I expect same from QSPICE.

[iMo]

Until Qspice can read the existing .asc files and libraries I doubt it comes to a significant move from LTspice to Qspice..

Frankly, I can hardly imagine someone who has been working with - for example LTSpice - will switch to the Qspice when all the existing LTSpice libs and .asc files are not readable and compatible (not talking here ADI and LT chip models, but general stuff). The Qspice has been created exclusively for Qorvo (as he did for LT in past), and until ADI acquires Qorvo  the reading in the .asc files will not happen, imho.

[Warhawk]

Until Qspice can read the existing .asc files and libraries I doubt it comes to a significant move from LTspice to Qspice..

Frankly, I can hardly imagine someone who has been working with - for example LTSpice - will switch to the Qspice when all the existing LTSpice libs and .asc files are not readable and compatible (not talking here ADI and LT chip models, but general stuff). The Qspice has been created exclusively for Qorvo (as he did for LT in past), and until ADI acquires Qorvo  the reading in the .asc files will not happen, imho.

The question is if there's somebody at ADI willing to update and understand LTspice for future. There's a good reason why TI has now pSpice for TI as the main simulation platform instead of Tina TI. If LTspice has not been updated for a while and has some limitations that QSPICE can address. Time will tell us.

[iMo]

ADI has released a new version recently (17.x.y) and the older XVII is no more supported (last update in Jan 2023).
Afaik MikeE is not working with ADi for 3 years already, thus it seems ADI does it alone.
And as wikipedia says he has written simulators since 1975, thus most probably ADI and Qorvo would insist on having sources and some know-how transfer to younger staff at their hand..
And worst case ADi will aquire the Qorvo, imho (and perhaps that is the Mike's business model behind)..

[SiliconWizard]

Until Qspice can read the existing .asc files and libraries I doubt it comes to a significant move from LTspice to Qspice..

Frankly, I can hardly imagine someone who has been working with - for example LTSpice - will switch to the Qspice when all the existing LTSpice libs and .asc files are not readable and compatible (not talking here ADI and LT chip models, but general stuff). The Qspice has been created exclusively for Qorvo (as he did for LT in past), and until ADI acquires Qorvo  the reading in the .asc files will not happen, imho.

Yeah, probably not. I'm suspecting that he did reuse a significant chunk of LTSpice's code (I can't imagine he would have rewritten a Spice simulator entirely from scratch), I already don't know for sure how he managed the IP matters with AD, or if there's going to be any down the line. Just wondering.

[gnuarm]

Until Qspice can read the existing .asc files and libraries I doubt it comes to a significant move from LTspice to Qspice..

Frankly, I can hardly imagine someone who has been working with - for example LTSpice - will switch to the Qspice when all the existing LTSpice libs and .asc files are not readable and compatible (not talking here ADI and LT chip models, but general stuff). The Qspice has been created exclusively for Qorvo (as he did for LT in past), and until ADI acquires Qorvo  the reading in the .asc files will not happen, imho.

Yeah, probably not. I'm suspecting that he did reuse a significant chunk of LTSpice's code (I can't imagine he would have rewritten a Spice simulator entirely from scratch), I already don't know for sure how he managed the IP matters with AD, or if there's going to be any down the line. Just wondering.

I doubt the option existed to use the LTspice code.  I seem to remember Mike saying, some time back, that it would not be much harder to code from scratch, than it would be to update the code to the way he wants it to be. 

[iMo]

..
Yeah, probably not. I'm suspecting that he did reuse a significant chunk of LTSpice's code (I can't imagine he would have rewritten a Spice simulator entirely from scratch), I already don't know for sure how he managed the IP matters with AD, or if there's going to be any down the line. Just wondering.

I would bet the IP stuff with ADI has been managed by Mike properly (he is an entrepreneur as well) and his Qspice is from 98% the LTSpice source.
He just threw out all ADI models (therefore it is not compatible with ADI's libs and models and it should not be till ADI agrees with Qorvo somehow) and traded it with Qorvo as well, imho.

[JohnG]

Don't forget that a significant chunk (most) of LTspice's code is highly likely to be Spice3/Xspice, which I believe is open source. So, Mike Engelhart would not necessarily need to have any agreement with ADI to start from that codebase.

John

[Smokey]

...
Got everything up and running (Build Aug 13).  And it looks like out-of-the-box the included libraries has support for..... only Qorvo JFETs, SiC Fets, and SiC Schottkys....   That's it.  It has generic behavioral stuff, but no other specific parts.

Yes, I understand that I can go find the spice model text definitions and paste them in.  They have a video demoing that here:

Code: [Select]

https://www.youtube.com/watch?v=WGJkZSDY9iA
But I really don't want to make symbols for everything with a sub-circuit... I wonder what the roadmap is for the default library...
I would think this would be something that could be hosted on github. Contribute with pull requests.  Merge libraries.  One community library.

I found where some of the built in models live (build Aug 25).  When you drop in a diode or a MOSFET or something like that, right click it and go to "selection guide".  That's where the built in models are.
So there is some stuff.  But it doesn't look like there are any opamps. 

[SiliconWizard]

Don't forget that a significant chunk (most) of LTspice's code is highly likely to be Spice3/Xspice, which I believe is open source. So, Mike Engelhart would not necessarily need to have any agreement with ADI to start from that codebase.

Almost all Spice-based simulators use more or less of the Spice3x source code, but that's far from making a complete, modern, marketable simulator.

Besides, in his interviews, Mike explicitely talks about how the original source code is a bit of a mess and relatively inefficient, so many have re-implemented a significant part of it.
And, there's also a lot of features implemented on top of pure Spice (like all the mixed-signal stuff).

But, anyone's free to try. You can start with the original Spice source code and see how it goes as far as making a simulator that can "compete" with LTSpice or the like.
These days, it would probably make more sense to start with ngspice, which is already a gigantic work past the original Spice. But even so, there would be a lot of work needed to make something that would remotely look like commercial software.

[iMo]

I got my first Spice in around 1988/9, on a single diskette (afaik 3G5, it was around 350kB large binary), for my Atari 520STM (8MHz 68k, 1MB ram). We tested it against the "mainframe" versions and we get identical results, to our surprise..
I ran a lot of sims at that time (a postgrad) and also I wrote a GFBasic (or what was the name of that Basic compiler) graphing app which read the long columns of numbers (the Spice generated) parsed them and draw nice auto scaling pictures (similar to today's graphics) I could printout on my matrix printer. I can remember a simulation of a CMOS logic element consisting of say 6 transistors with a transient analysis like 1us long (looking at single input and output voltages) took me perhaps 30minutes at that time.. 
I cross my fingers the Qspice and LTSpice will find a common path finally..

[JohnG]

But even so, there would be a lot of work needed to make something that would remotely look like commercial software.

For sure.

It is also a lot of work to recreate libraries.

I have played with QSPICE a bit. The ability to handle C code for a controller looks really powerful for some future applications of mine. But, at the present, I don't need it, so I find myself going back to LTspice because I have a substantial collection of libraries and circuits that I don't feel like recreating. It will be years before QSPICE has a decent set of libraries, I fear. I hope Qorvo and others have the patience to stick it out.

I'm a little leery of spending a lot of time on libraries and such just yet. I've been burned more than once having tools go away on me. Anyone remember the MathCAD debacle?

John

[b_force]

Just a pure practical question, but what are the benefits with yet another SPICE program?
Besides the many free alternatives that are already available?

[gnuarm]

Just a pure practical question, but what are the benefits with yet another SPICE program?
Besides the many free alternatives that are already available?

Mike used to be the "Spice guy" at LT.  LT was bought by ADI.  Don't know if there is a connection, but sometime later, Mike leaves ADI.  Now Mike is the "Spice guy" at... whatever his company is called.  So, yet another Spice.  At least, it shouldn't suck.

[SiliconWizard]

Another question is, what's going to happen to LTSpice? Sure they probably have other people to maintain it, but now that Mike is doing the same thing somewhere else, AD may not even have the right to get any help from Mike, just in case.

[langwadt]

the ability to make modules with verilog or C++ is quite interesting, trying to draw up even a modest amount of logic in gates it tedious when a few lines of verilog can do it

[magic]

Another question is, what's going to happen to LTSpice?

They don't need Mike to add models of new AD parts

[exe]

Just a pure practical question, but what are the benefits with yet another SPICE program?
Besides the many free alternatives that are already available?

I hope to see one spice that would be reasonably priced and wouldn't suck... I'm thinking to buy Tina because I had mostly positive experience with it and it has a lot of TI part (or I'm confusing it with Tina-TI?) which I tend to use instead of LT/AD parts nowadays due to AD parts being too expensive.

I also tried, uhm, PSPICE-FOR-TI. I'm still amazed how horrible UI of that thing was, and how big and slow it was, not to mention required online registration and that it doesn't work on Linux.

Still, up until now I find LTSpice the most reasonable simulator for my needs, though it has so much to be desired.

[ArdWar]

Decided to take a look, but wtf is going on with that "installer". It asks me if I want to install  in admin mode, but regardless of what I click or whatever windows compatibility options I run the installer to begin with it just run in circles asking me *again*, never actually installing....

[Warhawk]

Just a pure practical question, but what are the benefits with yet another SPICE program?
Besides the many free alternatives that are already available?

I hope to see one spice that would be reasonably priced and wouldn't suck... I'm thinking to buy Tina because I had mostly positive experience with it and it has a lot of TI part (or I'm confusing it with Tina-TI?) which I tend to use instead of LT/AD parts nowadays due to AD parts being too expensive.

I also tried, uhm, PSPICE-FOR-TI. I'm still amazed how horrible UI of that thing was, and how big and slow it was, not to mention required online registration and that it doesn't work on Linux.

Still, up until now I find LTSpice the most reasonable simulator for my needs, though it has so much to be desired.

TI has two simulation platforms. Tina TI is a strip-down version of Tina spice. I would not expect much happening with that tool. Pspice for TI a new strip-down version of cadence pSpice. It has the full pSpice functionality. If you add non-ti part, you have to have at least 1 maximum of 3 probes (that kinda sucks). I agree it is bloated.

[SilverSolder]

"This program is specifically not licensed for use by semiconductor manufacturers in the design, promotion, demonstration or sale of their products." 

Yep, banned at my job too. It is very annoying, but for my limited needs random online simulators do the job.

The license does not prohibit to use it by an employee of a semiconductor manufacturer at his home

I have a personal laptop with me that contain all the tools I like to use, completely independently of whatever environment I'm in.   Works for me!

[ataradov]

I have a personal laptop with me that contain all the tools I like to use, completely independently of whatever environment I'm in.   Works for me!

It is still a violation of the license if you are using it for work, even if it is installed  on your personal device. Whether you want to violate the license or not - up to you. I personally don't see the point.

[WatchfulEye]

Been playing with qspice for a bit this evening. Seems to work great, but I've found a strange issue with some 3rd party models.

I've found a few PMOS models which just don't work in QSpice, but work fine in LTspice. I still haven't completely worked out qspice, so can't be sure it isn't user error, but I'm certainly confused by the behaviour.

See attached images for the discrepancy. In the case of Qspice, the ZXMP10A13F model is completely non-functional, just a short circuit. This works as expected in LTspice.

[SiliconWizard]

Have you tried with removing the step param stuff?

[WatchfulEye]

Yes. That step param stuff is only to show both curves on one plot (I only added it for the benefit of the screenshots). The behaviour occurs with just the model used directly.

[magic]

If something doesn't work as expected you are probably better off asking on the QSPICE forum at qorvo.com, which is read by the author.

[JohnG]

I have a personal laptop with me that contain all the tools I like to use, completely independently of whatever environment I'm in.   Works for me!

It is still a violation of the license if you are using it for work, even if it is installed  on your personal device. Whether you want to violate the license or not - up to you. I personally don't see the point.

FYI, you can always contact ADI and ask for permission. Sometimes they give permission. I think the answer might depend on what kind of semiconductor business you are involved it.

John

[SilverSolder]

I have a personal laptop with me that contain all the tools I like to use, completely independently of whatever environment I'm in.   Works for me!

It is still a violation of the license if you are using it for work, even if it is installed  on your personal device. Whether you want to violate the license or not - up to you. I personally don't see the point.

I only use my personal laptop for personal work.  However, I may design things for personal use that later inspire designs at work.  This is completely legal, according to our corporate legal bods.

[SiliconWizard]

I have a personal laptop with me that contain all the tools I like to use, completely independently of whatever environment I'm in.   Works for me!

It is still a violation of the license if you are using it for work, even if it is installed  on your personal device. Whether you want to violate the license or not - up to you. I personally don't see the point.

I only use my personal laptop for personal work.  However, I may design things for personal use that later inspire designs at work.  This is completely legal, according to our corporate legal bods.

Yep looks fine.
Note that LT's (AD's) licensing restriction was likely primarily targetting uses by competitors rather than anything else. If you're working for a company designing semiconductors in a niche that has nothing to do with AD's offering, they (and their legal team) probably don't care whatsoever. Not saying you should risk it though.

[WatchfulEye]

Support is great.

A few minutes after contacting the author with my query, I had confirmation that it was an evaluation bug for certain MOSFET models, and a few hours later a fixed update was pushed out.

[16bitanalogue]

Another question is, what's going to happen to LTSpice? Sure they probably have other people to maintain it, but now that Mike is doing the same thing somewhere else, AD may not even have the right to get any help from Mike, just in case.

LTSpice will remain actively supported tool in ADI. There are no plans to sunset the program. Without delving into source details there was no love loss when Mike left ADI; at least from what I was told.

In fact the current team is the one who created the FRA tool.

[SiliconWizard]

Another question is, what's going to happen to LTSpice? Sure they probably have other people to maintain it, but now that Mike is doing the same thing somewhere else, AD may not even have the right to get any help from Mike, just in case.

LTSpice will remain actively supported tool in ADI. There are no plans to sunset the program. Without delving into source details there was no love loss when Mike left ADI; at least from what I was told.

Yes, I don't doubt it, and I know they have a software team that can maintain it.
But I was curious about how it has been all dealt with Mike, from IP to potential (even if just occasional) support, to any non-compete clause, etc. Maybe that's being too curious here. Just the fact he was "allowed" to leave and develop the same thing in a company that could be considered a competitor, or at least close enough to one, is interesting. Again these are maybe details that we are not supposed to learn about...

[16bitanalogue]

Another question is, what's going to happen to LTSpice? Sure they probably have other people to maintain it, but now that Mike is doing the same thing somewhere else, AD may not even have the right to get any help from Mike, just in case.

LTSpice will remain actively supported tool in ADI. There are no plans to sunset the program. Without delving into source details there was no love loss when Mike left ADI; at least from what I was told.

Yes, I don't doubt it, and I know they have a software team that can maintain it.
But I was curious about how it has been all dealt with Mike, from IP to potential (even if just occasional) support, to any non-compete clause, etc. Maybe that's being too curious here. Just the fact he was "allowed" to leave and develop the same thing in a company that could be considered a competitor, or at least close enough to one, is interesting. Again these are maybe details that we are not supposed to learn about...

My guess from my experience is that there was a 2 year non-compete clause. I signed one joining and then basically signed the same thing again when leaving my previous company. My stipulation was I could not actively recruit for 2 years; although, former colleagues could reach out anytime they wanted.
I am skeptical that non-compete documents can be any more specific to a particular product line.  I know many former colleagues working on amplifiers, converters, etc. that go directly to a competitor to work on designing the same type of products in the same space (mobile, automotive, aerospace). I imagine the only stipulation is "don't step on the previous company's patents".

I know ADI is extremely aggressive when defending patents, so as long as Mike is not stepping on those or any trade secrets he can create another Spice simulator with no legal ramifications.

Like Ray Ridley, I lament the fracturing of Spice - so many variations. Which one to pick? TINA-TI was my go to since it could solve transfer functions, but I have picked up LTSpice in recent years. It's actively supported by a large community; although, it does have it's own pitfalls. Ever run a bode plot on a converter? See you tomorrow morning!

[gnuarm]

Another question is, what's going to happen to LTSpice? Sure they probably have other people to maintain it, but now that Mike is doing the same thing somewhere else, AD may not even have the right to get any help from Mike, just in case.

LTSpice will remain actively supported tool in ADI. There are no plans to sunset the program. Without delving into source details there was no love loss when Mike left ADI; at least from what I was told.

Yes, I don't doubt it, and I know they have a software team that can maintain it.
But I was curious about how it has been all dealt with Mike, from IP to potential (even if just occasional) support, to any non-compete clause, etc. Maybe that's being too curious here. Just the fact he was "allowed" to leave and develop the same thing in a company that could be considered a competitor, or at least close enough to one, is interesting. Again these are maybe details that we are not supposed to learn about...

Wouldn't it be hard to claim harm by his "competition" since ADI doesn't sell LTSpice? 

The only thing they can claim with Mike, is if he copied code, which would be a copyright violation.  I can't think of anything else they could complain about.

[gnuarm]

Another question is, what's going to happen to LTSpice? Sure they probably have other people to maintain it, but now that Mike is doing the same thing somewhere else, AD may not even have the right to get any help from Mike, just in case.

LTSpice will remain actively supported tool in ADI. There are no plans to sunset the program. Without delving into source details there was no love loss when Mike left ADI; at least from what I was told.

Yes, I don't doubt it, and I know they have a software team that can maintain it.
But I was curious about how it has been all dealt with Mike, from IP to potential (even if just occasional) support, to any non-compete clause, etc. Maybe that's being too curious here. Just the fact he was "allowed" to leave and develop the same thing in a company that could be considered a competitor, or at least close enough to one, is interesting. Again these are maybe details that we are not supposed to learn about...

My guess from my experience is that there was a 2 year non-compete clause. I signed one joining and then basically signed the same thing again when leaving my previous company.

Why on earth would you sign anything on the way out the door???  What would be your incentive?

My stipulation was I could not actively recruit for 2 years; although, former colleagues could reach out anytime they wanted.
I am skeptical that non-compete documents can be any more specific to a particular product line.  I know many former colleagues working on amplifiers, converters, etc. that go directly to a competitor to work on designing the same type of products in the same space (mobile, automotive, aerospace). I imagine the only stipulation is "don't step on the previous company's patents".

That's enforceable without any paperwork.  That's what patents are about.  It is working on the same type of product that the courts have said can be enforced, direct competition using the previous employer's IP (such as trade secrets).  It's hard to show violations without being very intrusive, so the courts allow a direct ban from working on the same type of product.

I know ADI is extremely aggressive when defending patents, so as long as Mike is not stepping on those or any trade secrets he can create another Spice simulator with no legal ramifications.

Like Ray Ridley, I lament the fracturing of Spice - so many variations. Which one to pick? TINA-TI was my go to since it could solve transfer functions, but I have picked up LTSpice in recent years. It's actively supported by a large community; although, it does have it's own pitfalls. Ever run a bode plot on a converter? See you tomorrow morning!

There's always been no shortage of Spice tools to work with.  I don't think one more will be noticed, other than that it will be better in some way.

[16bitanalogue]

My guess from my experience is that there was a 2 year non-compete clause. I signed one joining and then basically signed the same thing again when leaving my previous company.

Why on earth would you sign anything on the way out the door???  What would be your incentive?

I don't recall all the verbiage, but that stipulation didn't concern me. In general it is a fair question, but one reason I would sign it with little concern is if I wanted to leave on good terms. I would choose not to be argumentative on my way out the door. I have seen plenty of people leave, and eventually find their way back.

[JohnG]

It is interesting that one of the most powerful tools in an EEs toolbox has turned into a sales/marketing tool...

I would say  > 90% of the EEs I know use LTspice. It is free, powerful, and it is easy to add models. Despite the (IMO) quirky interface (but fast, if you use it a lot), I think it made it to the top of the heap because they opened it up to third party models early on and did not put any limitations on design nodes, and they made the license pretty liberal in terms of usage. I'm sure some LT (now ADI) marketers are still losing sleep and gnashing their teeth about their failure to monetize this properly. However, I know that I have designs with expensive ADI parts because they were in the library, so I know they got a few sales out of it.

But, it's still Spice. Yes, LTspice probably has some proprietary algorithms, but I bet there are many ways around that. And, ADI/LT's product is not circuit simulators, it's ICs. I bet they are not real worried about Qorvo right now, because it not a big competitor in the IC realm. Maybe it will be someday, but not today.

Either way, suppose they lawyer up and try to quash Qspice. That would be expensive and what would it get? More ADI IC sales? I don't think they would spend the money to do this unless it started to look like Qorvo might threaten their core IC business. If that happens, i.e. if they actually feel threatened about ICs from Qorvo, they have bigger worries than circuit simulators.

In the meantime, Qspice looks really nice, but still rather buggy (though they seem to be working hard on cleaning it up). The C/VHDL capability might make it the killer app someday, but for now it is hobbled by lack of libraries.

Just my 0.02 in your favorite currency,
John

[gnuarm]

My guess from my experience is that there was a 2 year non-compete clause. I signed one joining and then basically signed the same thing again when leaving my previous company.

Why on earth would you sign anything on the way out the door???  What would be your incentive?

I don't recall all the verbiage, but that stipulation didn't concern me. In general it is a fair question, but one reason I would sign it with little concern is if I wanted to leave on good terms. I would choose not to be argumentative on my way out the door. I have seen plenty of people leave, and eventually find their way back.

To me, it is the exact opposite.  Why would a company want to be argumentative at the exit interview?  Any limitations, what so ever, for your exit, should have been presented at the hiring.  This is the sort of thing that would make me never want to return to a company.  I prefer honest companies.

[tggzzz]

I suppose I should RTFM or RTFAQ, but...

Does QSpice support IBIS models? That is one attraction of Microcap - not that I've use that either!

[SiliconWizard]

I suppose I should RTFM or RTFAQ, but...
Does QSpice support IBIS models? That is one attraction of Microcap - not that I've use that either!

I don't know either and haven't found the info with just a quick search.
But - I don't fully know QORVO's current offering, but if all, or most of their chips do not require IBIS modeling, why would they pay Mike for implementing this?

[tggzzz]

I suppose I should RTFM or RTFAQ, but...
Does QSpice support IBIS models? That is one attraction of Microcap - not that I've use that either!

I don't know either and haven't found the info with just a quick search.
But - I don't fully know QORVO's current offering, but if all, or most of their chips do not require IBIS modeling, why would they pay Mike for implementing this?

Points taken, but it would be a shame if QSpice was unnecessarily limited to a subset of application domains.

There does seem to be a tendency for different spices to be tailored to different classes of problem. On the one hand that can be positive: I like tools that do one thing well. On the other hand, having to choose between and learn conceptually similar but irritatingly different tools is a waste of brain power (e.g. trivially different word processors). On the gripping hand, it will probably remain an academic issue for me.

[SiliconWizard]

There are some simulators that support a wide range of features (including IBIS support, mixed-signal with the ability of writing user C or C++ code, etc), but they are commercial, expensive ones.
I guess the "free"/low-cost ones just don't have the teams/budgets to implement all of this.

ngspice - one of the "major" open-source Spice simulators - does implement mixed-signal sim and custom models in C but certainly the learning curve is a bit steep and the available GUIs are all pretty limited (at least compared to commercial simulators). I don't think it supports IBIS though, would have to better check. I remember that IBIS support in ngspice was a feature request for years, I don't think it has been implemented yet though, unless I missed it.

[soldar]

In the end it makes much more sense to write new software cross-platform from the start rather than relying on emulation nowadays.

I agree. I am running a few things with WINE but I have no intention of trying with more. If it ran with Linux I would give it a try but as it is I will give it a pass.

[SiliconWizard]

In the end it makes much more sense to write new software cross-platform from the start rather than relying on emulation nowadays.

I agree. I am running a few things with WINE but I have no intention of trying with more. If it ran with Linux I would give it a try but as it is I will give it a pass.

QSPICE doesn't run on Wine as I mentioned earlier, so even if you wanted to...

[SilverSolder]

You can always run it in a VM on any platform...  -  A very nice solution overall, in my experience.

[ledtester]

Has anyone tried it on a M1 Mac - perhaps by using Parallels?

https://www.zdnet.com/article/how-to-run-intel-windows-apps-on-an-m1-mac/

[Smokey]

Has anyone tried it on a M1 Mac - perhaps by using Parallels?

https://www.zdnet.com/article/how-to-run-intel-windows-apps-on-an-m1-mac/

The cross-platform thing is a directx support issue according to a post by Mike.

[huababua]

too bad that it doesnt run on linux. really really bad. feels like 1990.

[SiliconWizard]

Depending on DirectX for a new development of a Spice simulator (or just EDA stuff in general) is a bad idea these days IMO, and there are certainly many decent alternatives to get good antialiased vector graphics with good performance in a reasonably cross-platform way.

But we're not in Mike's shoes nor in Qorvo's head, and he may have had a particular reason for doing that.
That seems a bit odd, as he strived to make LTSpice run on Wine. Maybe he eventually got bitten by this (/fed up) and decided not to bother with that cross-platform compatibility at all for his new simulator.
Or maybe he thought it would take him too much dev time initially, so he strictly focused on Windows.

While IMO that was still acceptable 10 years ago, developing new software Windows-only (unless it's software that strictly concerns Windows users only) these days is a no-no and I wouldn't do that again.

[Warhawk]

Depending on DirectX for a new development of a Spice simulator (or just EDA stuff in general) is a bad idea these days IMO, and there are certainly many decent alternatives to get good antialiased vector graphics with good performance in a reasonably cross-platform way.

But we're not in Mike's shoes nor in Qorvo's head, and he may have had a particular reason for doing that.
That seems a bit odd, as he strived to make LTSpice run on Wine. Maybe he eventually got bitten by this (/fed up) and decided not to bother with that cross-platform compatibility at all for his new simulator.
Or maybe he thought it would take him too much dev time initially, so he strictly focused on Windows.

While IMO that was still acceptable 10 years ago, developing new software Windows-only (unless it's software that strictly concerns Windows users only) these days is a no-no and I wouldn't do that again.

Even though I expect that Mike has had fun developing the new simulation tool the main purpose is business for Qorvo. Providing a good simulation tool free of charge is the best marketing and the way to get some visibility. I know about Qorvo because of the QPSICE. Not the other way around. I started my professional career nearly 15 years ago. I've been in the semiconductor business last 8 years. I've been traveling worldwide visiting hardware teams. I likely met hundreds of engineers in tens of different companies. Never have I ever seen a single Linux desktop. I've seen few macs, mostly from management and procurement guys.
I occasionally use Linux myself but it is really a bad OS for getting any engineering done. No 3D cad, no 2D cad. Maybe the KiCad stands out but this has been mainly due to recent development when CERN stepped in. I don't see any reason why ANY company would invest extra efforts in Linux support. The business case is simply not there. Few exceptions and hobbyists won't bring $$$ to the table.

[huababua]

Understood. Of course there needs to be a business case behind everything.

But ever „modern“ software I am using is built on some kind of a cross platform. Shouldn’t be too much effort to set it up right and serve the three big player.

[magic]

I suspect there was little more reason than Mike being personally familiar with that API, and Qorvo not caring enough to push him away from it. For example, OpenGL would have made this software more wine-friendly and easier to port natively to OS X if a need arises.

Whether being Windows-only is a good business decision shall be seen in a few years. The position of Windows at electronics design companies is partly Microsoft's support for large scale enterprise deployments, and partly a matter of relevant software running on Windows simply because that's what customers have used so far. If Microsoft screws something up, or bean counters decide they don't want to pay for it anymore, or Apple leaves AMD and Intel in the dust, the industry may slowly shift away from Windows like others did.

If you look at software development for example, a lot of it is done on OS X or Linux and many if not most serious tools are already cross platform or "cloud" based.

[nctnico]

If you look at software development for example, a lot of it is done on OS X or Linux and many if not most serious tools are already cross platform or "cloud" based.

Indeed. It is rare for my customers to use Windows for software development. It is either Linux or Mac. FPGA development is another field where every self respecting manufacturer makes sure to have their tools running on Linux. Even small players like Gowin and Efinix. And a lot of higher end electronics software does run on Linux. Like Orcad Allegro, Sonnet, ADS, Matlab to name a few.

I suspect there was little more reason than Mike being personally familiar with that API, and Qorvo not caring enough to push him away from it. For example, OpenGL would have made this software more wine-friendly and easier to port natively to OS X if a need arises.

Using OpenGL directly won't matter much. And I don't see how drawing a few graphs would benefit from OpenGL anyway. Using a framework like wxWidgets (like Kicad does) or Qt makes it much easier to create cross-platform applications. wxWidgets is kind of like MFC (Microsoft Foundation Classes) so should be relatively easy to use for people used to programming Windows software in C++.

[magic]

I don't see how drawing a few graphs would benefit from OpenGL anyway.

First of all, you don't have to reinvent the wheel. The library is already written, you just tell it what to draw. As are GUI toolkits and frameworks, which likely use it under the hood for this kind of operations. Same for DirectX on Windows.

Secondly, GPU acceleration means faster speed and lower power consumption. OpenGL was originally developed for CAD, not for games.

[nctnico]

Using OpenGL is only benificial if you need to draw a huge amount of lines / shapes fast likes in a PCB design or mechanical CAD. There are downsides to OpenGL as well because in the end the OpenGL driver of the GPU needs to be implemented correctly (which isn't always the case). Also, not all VMs support OpenGL (like Virtualbox for example) and then you are back to software simulation (Mesa3D for example which isn't perfect). And then there is the move to Vulkan which spreads the development teams of GPU driver developers thin. All in all OpenGL is a speed optimisation but it does come at a price.

[Cyberdragon]

In the end it makes much more sense to write new software cross-platform from the start rather than relying on emulation nowadays.

I agree. I am running a few things with WINE but I have no intention of trying with more. If it ran with Linux I would give it a try but as it is I will give it a pass.

QSPICE doesn't run on Wine as I mentioned earlier, so even if you wanted to...

It does run. You need Wine Staging and set Wine Tweaks to "hide version" and it will run.

Not great though, it will simulate but it's super slow and buggy (the forground and background get set to black making the circuit invisible untill you change the color of everything). It is a graphics issue, it uses the GPU for simulating normally but on Wine it defaults to CPU only simulation and rendering making it take several seconds to even draw a trace, and the trace has artifacts in it. And yes, I tried Proton with DirectX to Vulkan conversion, and a bunch of settings, it just seems to ignore the GPU.

[SilverSolder]

On your Linux box, have a VM running Windows? -  The OS is an application, these days...   

[SiliconWizard]

On your Linux box, have a VM running Windows? -  The OS is an application, these days...   

You mean, like 60 years ago?

[SilverSolder]

On your Linux box, have a VM running Windows? -  The OS is an application, these days...   

You mean, like 60 years ago?

Nothing new under the sun...   -  I hear IBM wants to use AI to get rid of a lot of old code written in...   Cobol.

[SiliconWizard]

On your Linux box, have a VM running Windows? -  The OS is an application, these days...   

You mean, like 60 years ago?

Nothing new under the sun...   -  I hear IBM wants to use AI to get rid of a lot of old code written in...   Cobol.

The whole idea sounds like fun.