MUFF WIGGLER Forum Index
 FAQ & Terms of UseFAQ & Terms Of Use   Wiggler RadioMW Radio   Muff Wiggler TwitterTwitter   Support the site @ PatreonPatreon 
 SearchSearch   RegisterSign up   Log inLog in 
WIGGLING 'LITE' IN GUEST MODE

best circuit simulation software?
MUFF WIGGLER Forum Index -> Music Tech DIY  
Author best circuit simulation software?
headcleaner
anybody know whats best? or free and best even better? i had a quick look at spice but seems it only supports a hand full of ics and besides...better to know from peoples experience whats out there right?
is there anything that has a comprehensive set of ics - at very least op amps and 555 timers - better if all logic, counters, dividers, etc.

ive been trial an error soldering for ages but would like to go at some bigger ideas....

cheers
DGTom
My ghetto arse "simulation software" for logic type applications is the Nord G2 editor freware thingy.

For trying out sequencer ideas (logic, counters, dividers) its low level enough to be usefull in terms of ICs but also patchable enough to get an idea of how something can be used In Real Life.

Once I have an idea that something might be doable / useable / usefull I breadboard it & hook that into my modular via a tangled clump of croc leads.. I'm actually surprised at how quickly I can put stuff together on the BB now & generally stuff built from there works straight off.
sduck
I like to play with this one - free, needs java installed - don't know how comprehensive their part database is -
http://falstad.com/circuit/
citizen mori
http://bwrc.eecs.berkeley.edu:80/Classes/IcBook/SPICE/

wicked stuff.
daverj
headcleaner wrote:
i had a quick look at spice but seems it only supports a hand full of ics and besides...better to know from peoples experience whats out there right?


Most IC manufacturers have Spice models available for a lot of their parts. For example:

http://www.national.com/analog/amplifiers/spice_models
Tim Stinchcombe
headcleaner wrote:
anybody know whats best? or free and best even better? i had a quick look at spice but seems it only supports a hand full of ics and besides...better to know from peoples experience whats out there right?
is there anything that has a comprehensive set of ics - at very least op amps and 555 timers - better if all logic, counters, dividers, etc.

ive been trial an error soldering for ages but would like to go at some bigger ideas....

cheers
That's the sort of post that could run to several pages answering! SPICE comes in many different varieties, some free, some damn expensive. This list is possibly a little out of date, but it will give some idea of the vast number of programs out there:

http://www.terrypin.dial.pipex.com/ECADList.html

Unfortunately whilst they mostly share the same underlying 'calculation engine' (which is free, anyone can grab it and stick a GUI in front of it and try and sell it...), it's the front-end features that set them apart, and I guess the most general rule is 'you get what you pay for'. I.E. if it is free, it's quite likely to be a little low of special features. With any of them, you generally have to import the SPICE model libraries provided by the IC manufacturers; digital ICs are a different matter, as many SPICE program vendors have there own implementations, and this is where the men get sorted from the boys - some progs allow you to write simple models of the ICs, others don't, so the amount of time spent trying to get a model up and running can vary greatly.

Lots of people use Linear Techs free 'LTSPICE', but I have never tried it myself, though it is my understanding that it is quite capable. Personally I use SIMetrix AD Plus:

http://www.simetrix.co.uk/site/products/SIMetrix.htm

There is a node-limited free version available (which basically means after two or three op amps in a circuit it will be on its limit), but for a fully-featured licence you need to shell out 1,000s of dollars... That being said, it is very, very good, and will give things like PSpice and Intusoft (considered by many to be market leaders) a damn good run for their money.

The other thing to speak of since you mention it is the 555 timer. SPICE models for that chip are very hard to come by: you either try and simulate it with what's called a 'component level' model, which simply represents the IC with its equivalent internal transistors, diodes, resistors etc., but these are large and clumsy, and often don't run very well (giving 'convergence problems' to the underlying numerical calculations); or you try and build your own 'macromodel', which stitch together functional blocks which mimic the chips behaviour, but not necessarily exactly what is inside it. This is quite a good route to take, but it highlights one of the 'necessary evils' of SPICE - you must be prepared to spend some time learning how to use SPICE in itself, as well as simulating your circuits, i.e. there is a learning curve associated with using it.

All things being said, I find SPICE incredibly useful - it is a most invaluable educational tool, tool being the operative word, as you have to learn when it is/isn't appropriate to use it, and you have to learn how to interpret the results. I find I can bang a circuit into SIMetrix very quickly, in order to find out how it works/what it does etc., certainly many times faster than I could possibly to do on a breadboard. If you start out small, and grow naturally as your experience does, it can be very rewarding.

Executive summary: very useful, but you get out what you put in!

Tim
vintagesynthlab
I'm still getting to know LT-Spice after about a year of use.

I don't know if it is the learning curve (for the application itself), but I find it quite non-intuitive when it comes to setting up the criteria for Spice Directives, for example. Also, despite not having speciality parts for audio, I find that even the standard availability of part models are somewhat limited.
forbin
Have been using LTSpice for probably about ten years or so and it can horribly lead you down the garden path as in:

http://forbinthesynthesizer.blogspot.com.au/2009/01/spiced-up.html

But it can also really cut to the chase and allow you to understand (and debug) circuits so easily as in:

http://forbinthesynthesizer.blogspot.com.au/2010/06/it-lives.html
& a lot of the Berfotoron waveshaper... a WIP nemesis...

It is also a great tool for "what if I..." as in:
http://forbinthesynthesizer.blogspot.com.au/2013/06/stay-on-target.htm l

The ltspice yahoogroups have lots of models and some very knowledgeable people that can point you in the right direction. For me, personally, it is a very useful tool... and free!
slow_riot
As part of a set of tools and skills, simulation is invaluable, to me at least.

I use it as a drafting tool to check the viability of an idea, and then once I have a sketch, I move to protoboard to see what is *really* happening.

Some things are frighteningly accurate but there are too many pitfalls for it to be used as a substitute for real world circuit analysis. The ideal building blocks in the sim do not exist in real life.

Like everything, in the hands of the foolish it is dangerous...
Don T
sduck wrote:
I like to play with this one - free, needs java installed - don't know how comprehensive their part database is -
http://falstad.com/circuit/


I like this one as well. If you have a Mac, it has been compiled for OSX, and is available at the App Store, and it has been renamed iCircuit. It isn't free, but it's easier to use than the browser-based version, at least for me anyway.
chipaudette
For simple analog stuff like estimating gains, frequency response, and phase response, I use "5Spice Analysis" http://www.5spice.com/

It is free, but it is Windows only. It is also very limited in its depth, but that's also why it is very easy to learn and use.

Chip
horstronic
+1 for LTSpice.
It takes some time to fully understand how it works but it's totally worth it.
I'm doing all my circuit simulations with it.
JozeyWhales
National Instruments Multisim! It's a great graphics based simulation environment.
oldenjon
JozeyWhales wrote:
National Instruments Multisim! It's a great graphics based simulation environment.

+1 for Multisim (but the only other sim I've used is LTspice)
Sandrine
I use Spice and it's a bit goofy considering it's been a standard for 100 years now, but back in the day (DOS) I used Labview which was amazing for it's time. I have no idea how it is now because it's $1000 to $13,000 for a copy. Of course you can build airliners with it....
Neutron7
Tina TI is not bad but now you have to make an account to get it.
BananaPlug
Who's up on CMOS Tina Macros?

Tina represents many CMOS parts using Tina "macros" and the parts show up in the interface without power pins. They work though. The problem is that their outputs put out 5V even though my simulation is using +/- 15V power. Components I know do that are 4093 and 40106.

How can I change the voltage or add a power pin to these CMOS gates? I see some possible clues in properties menu but haven't figured out a solution.

Thanks
noservice
I'm using iCircuit to quickly test ideas. It's far from ideal or correct but it can be useful.
Synthiq
I have no experience with Tina, but in LTSpice I have been able to change the low and high output levels of the generic logic models by editing some of the parameters for the model, see below:



It's possible Tina similar functionality but you may have to read the documentation.
BananaPlug
I found a work around I can live with. The Tina editor has a tab for Sources. I used Sources >> Controlled Sources and set this expression to create a source that send 15V when the model's 0 to 1 value is high: (V(N1) > 0.5, 15, 0)

The expression goes in the sources properties (right click) at Operation Mode, VALUE, (click the three-dots button)

The source is represented as a box on the schematic with one in and one out. Just patch the gate's output through it. You can copy and paste these anywhere you like.

As simulation it's crap but it lets you pass along the voltage you hope to get in the real world and see what that does further down the line.

Here's the best lead I could find on the subject of these gates not modeling a specified supply voltage: https://e2e.ti.com/support/development_tools/webench_design_center/f/2 34/t/400610
NielsBakx
I second Falstad also.. been using it for a while, since I started immersing and learning about electronics and have found it an incredibly valuable tool. It does use idealised components so I have found anything that works in Falstad usually needs further tweaking once I put it on a breadboard.
Recently got a copy of LTSpice but haven't had enough time with it to give an informed opinion, but it seems like one of the standard go-to softwares.
MUFF WIGGLER Forum Index -> Music Tech DIY  
Page 1 of 1
Powered by phpBB © phpBB Group