Why are SPICE packages so bad?

Thread Starter

TechWise

Joined Aug 24, 2018
143
I would begin by saying this is not meant to cause offense or to slag off anyone or anything in particular.

Consider the software we need as electrical or electronics engineers, such as control simulation, PCB design, mechanical design, e-mail, word processing, thermal design, magnetic design, software IDEs, schematic capture and diagram creation. It strikes me that all of these offer some fantastic open source options and some really excellent paid-for options. KiCAD is one of the best open-source programs I've ever used, Altium Designer is just beautiful. I know a lot of people love Google Sketch-up, I love Autodesk Inventor. I pay for the Microsoft Office suite which I find very good, likewise I've used the free LibreOffice suite in the past and been impressed.

Then we come to SPICE simulation which in my humble opinion are universally horrible to use. I've used LT Spice, P Spice, TINA TI and Simetrix. All of them much the same with horrible appearances, bizzare keyboard shortcuts that differ from any other software, dated looking user interfaces and symbols. There's a hodge podge of different component libraries out there. I regularly find myself with a SPICE model for a MOSFET but a TINA-TI model for a gate driver and then wasting minutes and hours trying to simulate the two together.

Why is it the case that SPICE programs are so unpleasant to use? Clearly better methods of schematic capture exist, such as KiCAD. Clearly nice user interfaces can be done cheaply, such as LibreOffice. Clearly nice result plotting can be done, such as Matlab/Simulink.

I am genuinely curious about why no one has come out with a better piece of software. I regularly see huge multinational engineering firms advertise for jobs requiring experience with LT Spice or PSpice so there's a large market for these pieces of software. It's not like there's a shortage of electronic design engineers in the world that use them.
 

Alec_t

Joined Sep 17, 2013
11,796
Someone is looking into it. There is a thread somewhere (can't find it on this forum) inviting suggestions for improving LTspice.
Personally, I can forgive a clunky interface if the actual simulation is as accurate and as fast as the hardware will allow. It is wrong IMO for an indispensable tool to exalt fashion over function. A pretty interface could take up resources better used for the simulation.
 
Last edited:

jpanhalt

Joined Jan 18, 2008
10,920
Why is it the case that SPICE programs are so unpleasant to use? Clearly better methods of schematic capture exist, such as KiCAD. Clearly nice user interfaces can be done cheaply, such as LibreOffice. Clearly nice result plotting can be done, such as Matlab/Simulink.
To me, schematic capture is about going from schematic to PCB design. That is not what Spice is for doing. It's for electronic modeling, not drawing. As for MatLab, is it free to most users?

I am genuinely curious about why no one has come out with a better piece of software. I regularly see huge multinational engineering firms advertise for jobs requiring experience with LT Spice or PSpice so there's a large market for these pieces of software. It's not like there's a shortage of electronic design engineers in the world that use them.
How much did you pay for using the versions of Spice with which you have experience?
 
Last edited:

Papabravo

Joined Feb 24, 2006
14,831
I would say that good enough is the enemy of perfect. I have not seen any software package yet that was perfect out of the box and required no improvement, even the ones you have to pay for. So what is your plan to make things better? If anybody would share their code base, could you and your team pick it up and fork it? Maybe you think it would be better to start from scratch. Who is going to make new models for all those obsolete parts? There are economic incentives and disincentives in abundance. Who do you imagine can fix the problem? How would they go about doing it?
 
Last edited:

Thread Starter

TechWise

Joined Aug 24, 2018
143
To me, schematic capture is about going from schematic to PCB design. That is not what Spice is for doing. It's for electronic modeling, not drawing. As for MatLab, is it free to most users?


How much did you pay for using the versions of Spice with which you have experience?
I agree that the processes of concept->PCB are very different from concept->simulation. Clearly one would expect the schematics produced during the former to be of a much nicer quality because they may well be published as part of your documentation etc.

I know that MATLAB is very expensive indeed for commercial users but that was the point I was driving at. If commercial entities will pay large sums of money for really nice packages like MATLAB and Altium, I would have thought there would be a really nice SPICE package out there too.

Ordinarily, I would use LT Spice which is free of course. I also use a paid-for version of P Spice which I find similar in terms of awkward layout user interface. TINA-TI, which I also use, did not cost me anything but I assume it costs TI something and that they offer it as an incentive to use their products. I don't believe even a paid for version of TINA will have a drastically different UI.

I fully accept that when I do hobby work outside of my employment I will have to use whatever free tools are available to me. I just thought that if companies will pay huge sums of money to Altium/Mathworks/Autodesk then there would be premium SPICE packages out there too.
 

Thread Starter

TechWise

Joined Aug 24, 2018
143
I would say that good enough the enemy of perfect. I have not seen any software package yet that was perfect out of the box and required no improvement, even the ones you have to pay for. So what is your plan to make things better? If anybody would share their code base, could you and your team pick it up and fork it? Maybe you think it would be better to start from scratch. Who is going to make new models for all those obsolete parts? There are economic incentives and disincentives in abundance. Who do you imagine can fix the problem? How would they go about doing it?
I may have worded my original post poorly. I fully accept that when I am not at work, and I am working on private projects, I will have to use whatever free or budget-conscious software is out there. However, when I am in work, we are still often stuck with the same packages, purely because there doesn't seem to be anything nicer out there. My employer does pay large sums of money for access to premium quality schematic capture/PCB layout and also 3D modelling and FEA software. To my knowledge though, there are no premium SPICE offerings out there.
 

atferrari

Joined Jan 6, 2004
4,167
Someone is looking into it. There is a thread somewhere (can't find it on this forum) inviting suggestions for improving LTspice.
Personally, I can forgive a clunky interface if the actual simulation is as accurate and as fast as the hardware will allow. It is wrong IMO for an indispensable tool to exalt fashion over function. A pretty interface could take up resources better used for the simulation.
I believe that the request was not originated in the team maintaining LTSpice. I do not recall reading any formal/informal request by LT elsewhere.

His answer to my question was, "It well could be". Link here.
 
Last edited:

Thread Starter

TechWise

Joined Aug 24, 2018
143
Have you looked at CircuitMaker from Altium?
I've had a quick look just now but it looks like a Schematic Capture/PCB Layout type tool rather than a SPICE simulator. I already have a paid-for Altium Designer subscription so I'm not sure if CircuitMaker would be an advantage.

I've had a quick look at some YouTube videos on it and it looks like it has a really nice layout and modern UI.
 

MrChips

Joined Oct 2, 2009
22,481
Currently, I am using CircuitMaker 2000 (from Protel) which is schematic capture and simulator (Berkeley SPICE3f5/XSpice).
 

Thread Starter

TechWise

Joined Aug 24, 2018
143
I would say that good enough the enemy of perfect. I have not seen any software package yet that was perfect out of the box and required no improvement, even the ones you have to pay for. So what is your plan to make things better? If anybody would share their code base, could you and your team pick it up and fork it? Maybe you think it would be better to start from scratch. Who is going to make new models for all those obsolete parts? There are economic incentives and disincentives in abundance. Who do you imagine can fix the problem? How would they go about doing it?
Like any engineer I'll take function over form any day, however, I feel with these SPICE packages the UI is so clunky and unintuitive that it's a barrier to productivity. I know not everything is perfect out of the box regardless of price - the £20K scope we returned to the manufacturer recently is evidence of that.

I just think that going forward, simulation of gate drivers and wide bandgap devices and stuff of that nature is going to become more and more important. Clearly, SPICE type simulation is critical for studying that sort of transient behaviour in the detail required. Take, for example, an engineer working on an SMPS. They've got modern tools like Altium Designer, Autodesk Inventor, Ansys FEA and Code Composer Studio for their EDA, 3D modelling, thermal analysis and firmware development but when it comes to the SPICE simulation the available tools feel 20 years out of date.
 

BobTPH

Joined Jun 5, 2013
2,724
I actually find LTSPICE to the tool I can use to enter a schematic faster than of any other I have used, and that includes the package I wrote myself and use for PCB layout. Yes, it is not publication quality, but it is simple and intuitive. I have tried Eagle, Kicad and Diptrace and found them all to be very difficult to use for both schematic capture and PCB layout. Do not have any significant experience with any other SPICE program, and LTSPICE, does what I need, I really have no complaints.

Even though I have made a living off writing software development tools, I am not what I would call a tool guy. I have run into people who pride themselves on knowing every obscure feature of every tool. In a big org is actually helps to have one around, as he can answer any question about the tool.

Bob
 

ronsimpson

Joined Oct 7, 2019
1,121
When I started using SPICE you had to enter the schematic like this in a text editor. No graphics.
R1 N010 N040 16.9K
R2 N011 N043 3.4k
 
You think any of the SPICE programs are clunky? Try ECAP.

The screenshot is a PC version. When I actually used ECAP, it was on a batch basis running on an IBM mainframe, with punched cards and an ASCII-only printer as the I/O.ECAP.png
 

Thread Starter

TechWise

Joined Aug 24, 2018
143
When I started using SPICE you had to enter the schematic like this in a text editor. No graphics.
R1 N010 N040 16.9K
R2 N011 N043 3.4k
I believe you could still write a netlist file for PCB layout like that if you really wanted to.

I'm not one to mock the fundamentals. I learned an incredible amount about microcontrollers by writing a few programs in assembler. It makes you think about every decision and every connection. At the end of the day, Simulink is just a fancy UI that builds state-space models in matrices then solves them.
 

Thread Starter

TechWise

Joined Aug 24, 2018
143
You think any of the SPICE programs are clunky? Try ECAP.

The screenshot is a PC version. When I actually used ECAP, it was on a batch basis running on an IBM mainframe, with punched cards and an ASCII-only printer as the I/O.View attachment 204882
If the date on that copyright notice is anything to go by then I had only been around for two years!

I think as engineers become more and more removed from command-line interfaces and writing code that there will be real problems getting people who are prepared to put up with SPICE. I insist on programming my control in C-code as you have to think about every variable and every instruction. Already I have colleagues who rely on Simulink to write the code for them and hope for the best.
 

Reloadron

Joined Jan 15, 2015
5,714
With all due consideration to the software you mentioned in your initial post, both paid and open source let's think about something. When I began my career this software was my software and a big improvement. This software along with a slide rule (thanks dad) and being taught how to use it (thanks dad) was all there was and very much state of the art.

Templates.png

The stuff available today is better than what I had at my disposal 7 years ago when I retired. Considering what goes into creating a really good simulation the stuff available today is not really all that bad at all. Especially the free and open source stuff. I figure good things come to those who wait and software is no exception anymore than the machines to run it on. I know I have the lettering template around here somewhere. :)

Ron
 
Top