suggestion for a videoblog: David's view on simulation software - Page 1
Forum section: electronics / general

author: Nap0
author_rank: Newbie
timestamp: May 09, 2010, 06:02:46 pm
content: Hi,Just wanted to post a suggestion for a possible new video blog.I would like to hear David's view on simulation software, I don't think something like this has been covered yet?Could be both digital and analog simulation. The value or non value of such tools.Past experiences at work or in hone projects maybe?

author: Simon
author_rank: Unknown
timestamp: May 09, 2010, 07:07:05 pm
content: good idea, I have electronics workbench 5.2, very old but works, never got the ahem.. later version to work and I think it was very bloated

author: Nap0
author_rank: Newbie
timestamp: May 09, 2010, 09:41:50 pm
content: I use the freeltspice.I think it's quit good for general analog and power, but not suited for digital circuits.

author: EEVblog
author_rank: Unknown
timestamp: May 10, 2010, 03:03:13 am
content: I'd like to, but probably shouldn't for conflict of interest reasons.LTspice is currently taking the world by storm and is a great tool (and free).There are easier ones to drive though.Dave.

author: Simon
author_rank: Unknown
timestamp: May 10, 2010, 06:37:36 am
content: conflict of interests with who ?, if it is good it is good, or you can tell us which type of user the product is aimed at. I had a go with OrCad once and got no where because it was so complex to the point it took ambient temps into consideration. Then I got my hands on a modern version of EWB (now called spice or multisim or something like that). it was ok but much more complex than the old version I have

author: joelby
author_rank: Frequent Contributor
timestamp: May 11, 2010, 07:40:10 am
content: Quote from: Simon on May 10, 2010, 06:37:36 amHis employer.

author: joelby
author_rank: Frequent Contributor
timestamp: May 11, 2010, 08:25:42 am
content: Quote from: shafri on May 11, 2010, 08:24:37 amIt's a company that produces software which includes a software simulation component

author: EEVblog
author_rank: Unknown
timestamp: May 11, 2010, 12:09:27 pm
content: Quote from: joelby on May 11, 2010, 07:40:10 amCorrectamundo!Dave.

author: Simon
author_rank: Unknown
timestamp: May 11, 2010, 01:04:13 pm
content: well I suppose you could not review their software if it makes things awkward for you, at the end of the day if it is bad and it is best you not expose it as such not mentioning it makes it obvious that it is not worth using

author: joelby
author_rank: Frequent Contributor
timestamp: May 11, 2010, 01:24:12 pm
content: I don't think the conflict of interest is because there's anything wrong with the software per se.The problem is that you can't objectively review any competing software - if you say that some other product is bad, people will accuse you of doing so to promote your employer's product. If you say that your employer's product is bad, you may risk management being unhappy with you, or at worst losing your job. If you start raving about your employer's product, people will accuse you of bias.Simply put - it's easier to just not talk about it and avoid any problems.Why don't you try a few different simulation packages and write your own review?

author: Simon
author_rank: Unknown
timestamp: May 11, 2010, 04:08:19 pm
content: Quote from: joelby on May 11, 2010, 01:24:12 pmif you have a few thousand pounds to spare sure, I did actually get a quote for multisim, the student version was just over £ 1000 !I told the guy that it was more cost effective for me to breadboard it

author: armandas
author_rank: Frequent Contributor
timestamp: May 11, 2010, 04:31:44 pm
content: Quote from: Simon on May 11, 2010, 04:08:19 pmWow. Last time I checked, it was$39.95. Also, an evaluation version of Multisim is available. Not sure about other simulation software.

author: Simon
author_rank: Unknown
timestamp: May 11, 2010, 06:35:23 pm
content: there are deals for students but from what I can tell the package that replaces "electronics workbench" is very expensive for a hobbiest to buy, then they wonder why people download cracked versions, I know a lot of time goes into developing such programs but not everybody will make full use of all the intricate functions and I think that nowadays they all work around a core piece of software called SPICE ?, it would be great if a free-ware project was done for this sort of thing, I've seen a few attempts but nothing that really works for general purpose usage, really I'd like to see something that works like EWB 5.2 but is up to date and will run on Vista/7

author: dengorius
author_rank: Regular Contributor
timestamp: May 11, 2010, 07:01:15 pm
content: Quote from: Simon on May 11, 2010, 06:35:23 pmActually SPICE is free and open source and this is its original paperhttp://www.eecs.berkeley.edu/Pubs/TechRpts/1973/ERL-382.pdffrom Laurence NagelThe thing is that spice comes without a fancy graphic interface (the first version is from 1973) but it still is the engine of modern softwares such as PSPICE/OrCAD, LTSPICE etc.Personally i haven't had any problem with getting EWB up and running under Seven, not 5.2 though. Same goes for LTSPICE which is completely free

author: Simon
author_rank: Unknown
timestamp: May 11, 2010, 07:07:36 pm
content: well it would be nice if someone took the SPICE core and put an interface around it for free

author: allanw
author_rank: Frequent Contributor
timestamp: May 11, 2010, 08:47:06 pm
content: Quote from: Simon on May 11, 2010, 07:07:36 pmWhat's wrong with ltspice?

author: Simon
author_rank: Unknown
timestamp: May 11, 2010, 08:51:31 pm
content: well it is not the most intuitive

author: mkissin
author_rank: Regular Contributor
timestamp: May 11, 2010, 10:06:47 pm
content: Actually, after having tried a few SPICE products, I find LTSpice to be one of the fastest and easiest simulators to drive.Circuit entry is a breeze, with keyboard shortcuts for all of the basic components. Nothing is hidden from you, as the schematic translates directly into the SPICE listing. The graphical waveform output is also pretty intuitive.The only thing you could take issue with is that it forces you to get to know SPICE itself on a level that you wouldn't normally have to with other vendors' products. Personally, I feel that's a good thing. Nothing will lie to you quite like a computer simulation will, if you don't know how the underlying engine works.Finally, I have yet to encounter the sort of convergence issues that I was plagued with by other vendors offerings. As a general rule, if LTspice can't simulate my circuit, I've mucked it up somewhere.And it's free, with a complete library of essentially perfect models of Linear Technologies products.

author: joelby
author_rank: Frequent Contributor
timestamp: May 12, 2010, 04:43:01 am
content: Quote from: Simon on May 11, 2010, 07:07:36 pmPlenty of people have: gEDA, iSpice, gspiceui, etc. When I was at uni we used PSPICE 9.1 Student for Windows, which is freely available.I don't think it's possible for a GUI to make SPICE very simple (though GUI schematic capture is much better than editing netlists) as the systems it can simulate are complex, and it would be undesirable to hide all of the knobs, bells and whistles from the people who understand what they're for.

author: Simon
author_rank: Unknown
timestamp: May 12, 2010, 06:59:04 am
content: EWB 5.2 managed it fine, you could have an option to "unlock" those variables if needed. if i'm testing a theoretical design in the early stages possibly on virtual parts (no part number specified) I hardly need to consider temps right ? where do i find those free simulators you were referring to ?

author: joelby
author_rank: Frequent Contributor
timestamp: May 12, 2010, 07:03:45 am
content: Quote from: Simon on May 12, 2010, 06:59:04 amMaybe not, but maybe you do? It's actually nice to know that your model isn't assuming your components are 'perfect' if you're planning to build it - it can save a lot of time of wondering why things that simulate well don't actually work in practice.Anyway, just Google the names of those programs - they'll be the first or second hit.

author: Simon
author_rank: Unknown
timestamp: May 12, 2010, 11:47:11 am
content: both theoretical models and real models are useful, when i did have my cracked version of multisim working I could not figure out why a led did not light. it was because I was not putting over 10 mA through it, that was not a realistic approach as I've run leds at 5 mA in the real world, it helps to be able to test you idea and then test it for practicalitymaybe Dave could review the free versions then, after all no hobbiest and few small businesses are going to spent £1k+ on commercial stuff