SPICE Netlist Simulation Using NI LabVIEW & NI Multisim

Do you have an old library of SPICE files or new ones from other circuit design software like KiCAD you'd like to simulate or analyze or vice versa? Would you like to modify the circuit inputs in real-time and see the outputs as a result?

Here is a step-by-step process to run text-based SPICE netlist simulations from NI LabVIEW. NI Multisim is used as the simulation engine and it is run in a background process connected to LabVIEW using the LabVIEW Multisim API Toolkit.

 Create and modify a netlist file from a Multisim circuit file

 Create and modify a SPICE nutmeg command file

 Use LabVIEW to build a VI that will execute the SPICE nutmeg command file

 Display results from the simulation

Nutmeg is a post processor for SPICE it takes the raw output file created by spice -r and plots the data on a graphics terminal or a workstation display.

The PDF is attached for advanced users of National Instruments who would like to design the Multisim circuit and LabView block diagram on there own.

For the rest of us, we will use the prebuilt sample files provided to simply "Run" the SPICE files for analysis.

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Requirements

 NI LabVIEW 2013 or higher

 NI Multisim 14.0 or higher (Power Pro or Education Editions)

 LabVIEW Multisim API Toolkit (installed by Multisim)

 Files in the SPICE Command Line folder located in the Multisim samples folder

In a typical Multisim installation, the samples folder is in this location:

C:\Users\Public\Documents\National Instruments\Circuit Design Suite <version>\samples\LabVIEW Multisim API Toolkit\

I am currently running Multisim 14,3 so my files were located here:

C:\Users\Public\Documents\National Instruments\Circuit Design Suite 14.3\samples\LabVIEW Multisim API Toolkit\SPICE Command Line

Another way to find the samples folder in Multisim is to select File»Open samples, and take note of the folder location in the explorer window.

Open the Spice Command Line ms design file.

Open a blank design.

Next, open the prebuilt vi. The file name is SPICE Command Line vi

To view the block diagram click the "Windows" tab then select "Show Block Diagram" from the dropdown menu in the LabView Front Panel.

To simulate the SPICE Command Line in LabView click the white arrow icon. The transient acquisition graph will start to populate the data from the Multisim circuit.

 The log of the results is saved in a RawData.tmp file.

See the LabView block diagram to see how this is accomplished.

Two subVIs:

1. sub Create Local Paths VI and
2. sub Data Parser VI

which are custom made, allows you to create your own if you wish, or for convenience use these subVIs provided.

_________________________________________________________________________________________

Here is what my RawData.tmp file looks like for points 1-5 and 439-447:

Title: ** SPICE Command Line **

Date: Sun Feb 5 03:19:25 2023

Plotname: Transient Analysis

Flags: real

No. Variables: 3

No. Points: 448

Variables:

0 n1 time time

1 n2 voltage V(input)

2 n3 voltage V(output)

Values:

 0 0.000000000000000e+00

0.000000000000000e+00

0.000000000000000e+00

 1 2.000000000000000e-09

0.000000000000000e+00

0.000000000000000e+00

 2 4.000000000000000e-09

0.000000000000000e+00

0.000000000000000e+00

 3 8.000000000000000e-09

0.000000000000000e+00

0.000000000000000e+00

 4 1.600000000000000e-08

0.000000000000000e+00

0.000000000000000e+00

 5 3.200000000000000e-08

0.000000000000000e+00

0.000000000000000e+00

439 9.613238626197609e-06

5.000000000000000e+00

4.435451045444346e+00

 440 9.653080484181489e-06

5.000000000000000e+00

7.191203675414505e+00

 441 9.702830176830998e-06

5.000000000000000e+00

7.866990590203802e+00

 442 9.742089605972989e-06

5.000000000000000e+00

6.587204646765869e+00

 443 9.787203930557956e-06

5.000000000000000e+00

5.138618203987046e+00

 444 9.831838995192895e-06

5.000000000000000e+00

4.570024884251302e+00

 445 9.883862443507754e-06

5.000000000000000e+00

4.328877880904384e+00

 446 9.939326395757750e-06

5.000000000000000e+00

4.188376596821053e+00

 447 9.999999999999999e-06

4.999999999957648e+00

4.738785809050968e+00

Multisim also has an Arbitrary SPICE Block.

The Arbitrary SPICE Block is a special portless component that allows a netlist to be inserted directly within the simulation netlist. The Arbitrary SPICE Block provides the same SPICE/XSPICE support as inherently supported in NI Multisim, including PSpice device and parameter support.

How to Import a Netlist Using the Arbitrary SPICE Block:

1. Open the Component Browser (Place > Component)
2. In the Basic group, Basic Virtual family, select the Arbitrary SPICE Block and click OK
3. Left-click to place the component on the schematic
4. Double-click on the component to invoke its Component Properties
5. Paste the SPICE netlist to be simulated.
6. Click OK

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000YG0ACAW&l=en-US#:~:text=The%20Arbitrary%20SPICE%20Block%20is,PSpice%20device%20and%20parameter%20support.

Also, here's the link to see how you can use SPICE models in KiCAD.

Ready to try simulating SPICE models? Here are some resources in no particular order:

Analog Devices

Microchip

LittleFuse

Kyocera