Symbolic circuit simulator exist?

[div]

symbolic circuit simulator

Hi there:

Sometimes, I need to find the multi-port Z(Y,S,T) matrix
from a circuit netlist (Spice netlist).

Then the questions are:
1) Can circuit simulator(Hspice) give a multi-port Z(Y,S,T) matrix
output?
Suggestions as how to combine several 2-port matrix into
multi-port matrix technique are also welcome.

2) I not only want to find the numerical solution but also
want to find a symoblic solution. Is there any circuit simulator
being able to do that?
For example, I have a 2-port network as below
--L ------L--
|
C
|
---L ------L--

I can manually calculate the Z(Y,S,T) matrix with a
symbolic expression. But how about a network with
hundreds passive elements? Any suggestion/idea?

If there is no such kind of tool, I may consider to
write a freeware to do that. )


Thanks
Div

 

[the_penetrator]

symbolic circuit analysis

Yes, such tools exist. You should be looking for SNAP or Sapwin. Especially Sapwin has the feature you request.

Personally, i have used only the DOS-based XFUNC tool, which comes with source code and can be found at www.simtel.net and other places.

It comes from 1991, and it supports basic elements like dependent and independent current or voltage sources, ideal opamps, R-L-C etc. With these things you can build many things, like AC equivalents and so on.

All these calculate Laplace transfer functions etc

the_penetrator©

 

[flatulent]

symbolic circuit solver

Another general purpose method is to use a SPICE simulator to perform the measurements that define the parameters you want. Drive a port and terminate all other ports with what the N port parameters require and then find the voltage, current etc and do the division. PSpice will allow frequency sweeps and math calculations in the probe window so that you can get a graph of the parameter in either rectangular or polar form.

 

[Nobody]

sapwin symbolic

http://www.analog-insydes.de/
It use mathmatica to calculate circuits in symbolic form .
There's one demo program to show its features .

 

[Humungus]

ti 89 circuit simulator

Hi all,

There are also other tools. There is a special module for Maple caled Syrup. A collegue use it, getting quite impresive results.

ISAAC from the KUL is also a solution. Is a little heavy to use it but once you get the hint there is no problem. Results are shown in Matlab-like form.

Some time ago I also heard about Symbolic Spice. Never seen it. Try it and tell us;-)

Regards

Humungus

 

[the_penetrator]

spice xfunc

Dear humungus and other fellow posters,

sspice (Symbolic Spice) is very nice, but left to a demo version (SSPICE1.0). It can handle up to 6 analog nodes. Which permits only 2-4 transistors in the circuit.
Look here: h**p://www.simtel.net/pub/pd/45184.html

The TI calculators had some minimalistic symbolic circuit analysis tools but you have to run a dongle emu in addition to the TI-calc emulator.

For XFUNC (helped me a lot!): h**p://www.geocities.com/hyiu00/ (may not work) and at simtel: h**p://www.simtel.net/pub/pd/24228.html

Regards,
the_penetrator©

 

[div]

characteristics of circuit simulation matrices

The Syrup is here from Maple(R)
**broken link removed**

Humungus:
Could you give more links about ISAAC?

Thanks
Div

Hi all,

There are also other tools. There is a special module for Maple caled Syrup. A collegue use it, getting quite impresive results.

ISAAC from the KUL is also a solution. Is a little heavy to use it but once you get the hint there is no problem. Results are shown in Matlab-like form.

Some time ago I also heard about Symbolic Spice. Never seen it. Try it and tell us;-)

Regards

Humungus

 

[Humungus]

maple syrup symbolic circuits analyzer

hi,

This is a link to the ISAAC page

**broken link removed**

At the end of the page there is an email address.

I don't know if it is free.

 

[mems123]

symbolic simulator isaac

Hi,
With pspice softawre you can simulate circuits, using Schematics of circuiit.

mems123

 

[goodboy_pl]

spice netlist maple 6

Dear friends,
i think normally, symbolic(analytic) analysis is not used large circuits-because of very large equation which is not handeable by human brain!,so it is possible to use demo version of soft.
also it is possible to write node-admitance matrix and give it to maple or mathematica to solve it but with a small care to do this without any bug!

another advatage to use a mathematical app. is that usually analytic equation is written to know the behavior of the circuit,and/or to optimizing it,so u can use the ability of such apps. to derivate the equations and solve them.

best...

 

[ulderico]

symbolic cirucit

whit tinapro is possibile a few type of simboloc simulation

 

[the_penetrator]

symbolic circuit analysis netlist

to mems_123: pspice does many things but never symbolic analysis of circuits: To produce transfer functions given symbolic names to parasitics.
Gives NUMERICAL not ANLYTICAL solutions. There might be way to do parameteric sweep to overcome this and use Excel and ... but that goes too far.

to goodboy_pl: i agree. I had a current conveyor (the idea popped up from Sedra's PhD!) CCII actually. It consisted of 20 transistors, however i had to use only 6 plus ideal sources and simplifying stuff to get accurate description of some characteristics. (Gain and input resistance).

the_penetrator©

 

[mwpro]

two ports networks simulation with maple

Agree that symbolic ones are usefull for small and simple circuits. For less simple ones, even after the nodal equations are solved, you still get very complex expressions which cannot be handled with cleaver approximation and substitution.

regards,
mwpro

 

[Dalibor]

symboloc spice

Yes, look here: http://snap.webpark.cz

 

[flyhigh]

ti-89 simulation symbulator

Hi,

I would like to know if some of those symbolic solver can handle distributed elements such as transmisson lines and other usual RF/MW elemetns and output S, ABCE or T matrix?

flyhigh

 

[costox]

ti-89+network 2port

wHAT IS the best symbolic circuit solver does anyone know ?
(Maple, Mathematica ? ... etc)

 

[adel_48]

simbolic circuit simulator

Hi

There is also a small symbolic simulator for TI-89 and TI-92 calculators. it is called symbulator. I used it for some time and it was rather fast (than solution by hand of course) and very handy