I am trying to simulate the 810911001 line filter (Wurth Electronik) on LTSpice which I downloaded on the following link :


I tried to simulate the circuit but I do not have the same result which is written in the datasheet for 50 ohm / 50 ohm sym :


Thank you for your time.

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    \$\begingroup\$ What is the expected result and what is your result? \$\endgroup\$ – The Photon Mar 20 at 19:27
  • \$\begingroup\$ It's only a simulation, so unsurprisingly its not identical. Attenuation seems to peak at ~1.1MHz and then reduces by ~15dB between 1MHz and 20MHz, which is not shown in the datasheet. Is that what you found? Unfortunately the library file is encrypted, so it could be hard to figure out what is 'wrong' with it. \$\endgroup\$ – Bruce Abbott Mar 20 at 20:10
  • \$\begingroup\$ Yes Bruce, the simulation peak is around 1.1 MHz whereas it is around 10 MHz in the datasheet. Moreover, around 10 kHz I have 6 dB and not 0 dB. PS : I have 50 ohm for the generator and 50 ohm for the load. \$\endgroup\$ – Damien31750 Mar 20 at 22:04
  • \$\begingroup\$ Wurth's models are good, but not perfect. You're also simulating parasitics, which should not be for datasheet testing, but they don't affect the result much. I'm afraid that's what you get with this model since, as mentioned, their models are encrypted. \$\endgroup\$ – a concerned citizen Mar 22 at 12:59

Agreeing with the comments that sims are not exact, you probably want to balance your parasitic cap, you currently only have 1 output leg with a cap, add one to the other side to balance.

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  • \$\begingroup\$ I added resistor and capacitor on each wire, the result is better around 10 kHz. Exactly, I know I can not have the same result but I find difference between frequency peak big. \$\endgroup\$ – Damien31750 Mar 21 at 11:49

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