I analyzed the CMC choke by Wurth Electronics (part no: 744830039080) using VNA and obtained the insertion loss for both common mode and differential mode.

common mode insertion loss

Differential mode insertion loss

The graphs match with the datasheet:

Insertion loss from Datasheet

While attempting to replicate the data in LTspice, the downloaded SPICE file from Wurth did not produce multiple peaks or resonances as shown in the datasheet graph:

Spice simulation for Single resonance of common mode connection in comparison with library file

I was able to optimize the common-mode impedance with the datasheet for the first resonance peak. How can I optimize the graph to reflect the measured results accurately with multiple resonances?

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    \$\begingroup\$ Alaska - Hi, Currently your question breaks the site rule on referencing material copied/adapted from elsewhere. To comply with that rule, please edit the question & add the name of the PDF / video / webpage (in this case, it's a datasheet, so probably a PDF) which is the source of the graph, and its link. Also please remember it's your responsibility to follow that rule in future too. TY (Please see the tour & help center as site rules here differ from typical forums.) \$\endgroup\$
    – SamGibson
    Mar 6 at 7:34
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    \$\begingroup\$ Does this answer your question? Multiple resonance frequencies of common-mode choke While the question is not really a duplicate, it turns out the one answer covers, quite possibly, everything you're looking for and more(!). \$\endgroup\$ Mar 6 at 8:47
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    \$\begingroup\$ I don't have an IEEE membership, but if you do I believe these papers might be relevant: ieeexplore.ieee.org/document/7468314 ||| ieeexplore.ieee.org/document/9862235 \$\endgroup\$
    – Ste Kulov
    Mar 6 at 9:34


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