Mike Engelhardt's new SPICE simulator QSPICE is out

[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?