Matlab + Simscape vs NI Multisim - Page 1
Forum section: electronics / beginners

author: Metonymy
author_rank: Newbie
timestamp: January 06, 2018, 06:45:55 pm
content: Hello,I'd like to invest in a simulation software in order to understand and to experiment with circuits.I'm thinking about: NI Multisim Student or Matlab Home + Simulink and Simscape, however I don't have any experience with them.Which tool would be better for me?

author: rstofer
author_rank: Super Contributor
timestamp: January 06, 2018, 08:45:12 pm
content: I haven't used Multisim, primarily because they don't seem to have a 'Home' edition. Maybe my grandson will buy it when he starts EE school next fall. Then I can play with it!I have used Matlab/Simulink mostly to play with differential equations. I can set up an analog circuit (op amps and gain blocks) to model the equations and then run the simulation. I can even add 'dials' to set the various parameters. I haven't used Simscape although I do have it. I just haven't had an application.Another thing to consider about Matlab is that it does ordinary mathematical things. One example is solving the simultaneous linear equations that result from mesh or nodal analysis. Matlab does some really heavy duty computing for those folks that are far above my pay grade. Deep learning, computer vision, and a lot more. It is a powerhouse!There are other tools: For mathematics, wxMaxima, Octave, Maple and Microsoft Mathematics do nice work. I use wxMaxima a LOT. AFAIK, all of these are free.A couple of books for Matlab that you might like:"MATLAB A Practical Introduction To Programming and Problem Solving (Fourth Edition)" - Attaway"Solving DC and AC Circuits By Example Using Matlab" - Haskell and HannaFor wxMaxima (Maxima) and Physics:"Classical Mechanics With Maxima" - TimberlakeFor electronics, LTspice is a terrific simulator and it's free.

author: Metonymy
author_rank: Newbie
timestamp: January 06, 2018, 08:48:04 pm
content: Thank you! NI Multisim has a student edition which is pretty cheap.

author: rstofer
author_rank: Super Contributor
timestamp: January 06, 2018, 09:14:04 pm
content: Quote from: Metonymy on January 06, 2018, 08:48:04 pmAh, yes! To be a student again... Laying in the grass and watching the girls walk by. Alas, I could be as old as 4 students combined!Enjoy it while you can! I did...

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 06, 2018, 10:38:04 pm
content: I forget what MATLAB's student/private licensing is down to, these days; it might be competitive.I never got the feeling it was a very practical environment for circuits. I don't think they have a solver as advanced as SPICE; but they might've changed things a lot since then, and my experience was with Simulink, not Simscape. Simulink, yes you can select and build components, assemble circuits, and simulate them, but it's a lot more janky than a proper schematic capture system, and IIRC only supported fixed timestep Newton integration (which is to say: only as good as Falstad web simulator(!)).Multisim (v11 was the last I used) is a fine SPICE environment, and like all(?) low budget/free simulators, is based on XSPICE (with some PSPICE compatibility/extensions, and a proprietary digital code language, because nobody actually likes XSPICE's digital primitives).If you're wondering, "low budget" includes Altium (which has the same base, different extensions). Go figure...As such, it includes all the drawbacks that the ancient XSPICE backend offers. Get used to adjusting simulation parameters.It's not very suitable for large (multi-sheet, hierarchical) designs, but it is quite possible to realize complete designs, from entry, to simulation, to layout (via Ultiboard, if provided).Tim

author: Vtile
author_rank: Super Contributor
timestamp: January 06, 2018, 10:39:03 pm
content: Quote from: rstofer on January 06, 2018, 09:14:04 pmJust move to sweden and enter for a degree for free again.Matlab is the bee's knees for control theory.

author: IonizedGears
author_rank: Regular Contributor
timestamp: January 06, 2018, 10:45:10 pm
content: MATLAB has a pretty powerful analog transfer function library and analysis tools that makes analyzing filters pretty easy so long as you can do the math to get the transfer function. It also has pretty powerful tools for DSP.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 06, 2018, 10:52:10 pm
content: Quote from: IonizedGears on January 06, 2018, 10:45:10 pmIf nothing else, AC analysis is just complex vector math -- something trivial to do in MATLAB and Octave (free/GNU).Tim

author: filssavi
author_rank: Frequent Contributor
timestamp: January 06, 2018, 11:01:03 pm
content: MATLAB/simulink and NI multisim(spice) are two very very different beasts targetted at two very different design stages and wanting to follow a model driven design approach you'll shurelyend up using both on the same project.In power electronics where I work for example MATLAB/simulink is best used in the first stages of the design whey multiple converter topologies are evaluated, typically the system will be modeled at the highest level possible, that means electrically ideal switches (power losses are accounted for separately) ideal connections/pcb layout and so ononce you are confortable with the simulated system performances you will transition to SPICE (be it multisim, ltspice, orcad/pspice, etc) where you will simulate only few switching cycles to see what a more realistic voltage/current wavefom will look like..so the two systems are complementary and not in competitionyou also have to distinguish between simulink/simescape and the proper MATLAB programming/scripting language, since for the latter there are multiple valid Free and open source alternatives, the most competitive one in my opinion is the python scientific ecosystem (to get started take a look at one of the pre-made distributions like anaconda or enthought)

author: Vtile
author_rank: Super Contributor
timestamp: January 06, 2018, 11:01:46 pm
content: Also another free and rather simple and powerful math tool is xcas, while not circuit analysis tool as such it is handy to have a good symbolic math tool.https://en.wikipedia.org/wiki/XcasPS. Free competitor like said above in python environment is also the SciLab, which is kind of an Matlab alternative.