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So this is a somewhat complicated question... I am trying to run a .op simulation (DC operating point), using the .step command to iterate through a bunch of component values. I would like to save the output as a series of text files. Information that must be saved for each run:

  • the component values in each .step instance
  • the corresponding voltage at a specific node

Each run can be output in a separate text file, that's fine, but if it's possible I would like to just have 1 text file with the key info from each run separated by a few lines.

Is this possible?

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So I've been trying to use the .meas command to print data to the error log, but it doesn't seem to work as advertised and I don't understand why. Here's an example of a resistor divider where I step one of the resistors and want to print the divider voltage values. For some reason .meas doesn't output the requested data?

R1 Vout 0 {rVariable}
R2 N001 Vout 1k
V1 N001 0 1
.step param rVariable list 1k 3k 9k 12k
.meas V(Vout)
.op
.backanno
.end

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OK, I have just now figured this out. Here's what I did:

  • I ran the stepped simulation for the operating point.
  • I then selected the graph drawn by the .meas command.
  • Going to the File menu, I selected "export" and then V(Vout)
  • This generated a txt file with the data points I wanted.

Unfortunately this doesn't seem to actually output the variable selected by .meas yet, but I'm confident that that can be solved soon.

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Well, I've did some more reading and found people claiming that the .meas command doesn't work with the .op command, it has a bug and will only print the last value from a .step sequence. Is this true? Does anyone know of a workaround for this problem?

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    \$\begingroup\$ Is the .meas command helpful? \$\endgroup\$ – PlasmaHH Oct 25 '16 at 19:29
  • \$\begingroup\$ @PlasmaHH is correct. You can see the results of the measurement in the Error Log (Ctrl + L from memory). \$\endgroup\$ – Matthew Oct 25 '16 at 19:39
  • \$\begingroup\$ OK, I am reading up on this command. I will let you know how it goes. Thanks for pointing me in the right direction! \$\endgroup\$ – Colin Marcus Oct 25 '16 at 19:52
  • \$\begingroup\$ After the .meas you can read the log file (Ctrl+L), then RClick and select "Plot stepped data". After plotting, if you so desire, you can also export your waveform as data. \$\endgroup\$ – a concerned citizen Oct 26 '16 at 7:06

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