I downloaded the PSpice model of the UCC25800 from here. I then tried to create a model for LTspice by opening the .lib file within the folder and then creating a symbol in LTspice.

But, when I opened the .lib file in LTspice, it seemed to be corrupt; there are random numbers in the file. It doesn't make sense and doesn't work after symbol creation. Is the .lib file corrupt? Or is it an error on my part?

Note: the model is from TI.com and not from any third party.


2 Answers 2


Look at the very top line: -

* UCC25800-Q1
* (C) Copyright 2022 Texas Instruments Incorporated. All rights reserved.                                            
** This model is designed as an aid for customers of Texas Instruments.
** TI and its licensors and suppliers make no warranties, either expressed
** or implied, with respect to this model, including the warranties of 
** merchantability or fitness for a particular purpose.  The model is
** provided solely on an "as is" basis.  The entire risk as to its quality
** and performance is with the customer

Do you see that the file is encrypted. This means that all the random numbers you see are in fact the encrypted spice file data. You have to use features in LTspice to unencrypt the data. You still won't be able to see the unencrypted information but, it should run on LTspice.

Don't ask me how to do this because I don't use LTspice. If you can't get it to run on LTspice there's a chance that it will work with Micro-cap. I say this because I've used encrypted files from ON semi with Micro-cap.

  • \$\begingroup\$ Thank you. I will read about that, and I will let you know. \$\endgroup\$ Commented Nov 26, 2023 at 14:18
  • \$\begingroup\$ Yes. I apologize. Could you please consider removing the downvote from the other answer? I find its contents to be useful. I will make sure not to be careless again. \$\endgroup\$ Commented Nov 26, 2023 at 16:17
  • \$\begingroup\$ @Jonathan_the_seagull I have removed the d/v from your question because it got edited a few minutes ago and this allows me to remove the d/v however, for the instructions given by Chester, someone has to edit his answer (a trivial edit would do) before I can do the same. \$\endgroup\$
    – Andy aka
    Commented Nov 26, 2023 at 16:35
  • \$\begingroup\$ Thank you for your understanding. An edit has been made to the post. \$\endgroup\$ Commented Nov 26, 2023 at 16:45
  • 3
    \$\begingroup\$ I'm pretty sure it's not possible to use a PSpice-encrypted model in LTspice. You have to have either an LTspice-encrypted model or an unencrypted model. \$\endgroup\$
    – Hearth
    Commented Nov 26, 2023 at 16:49

From a comment:

Is it possible to decrypt the .lib file for use in LTspice?

Since the Pspice model in the question is from TI, performed a search on the TI forum which gave:

  1. Decrypt PSPICE MODEL of ST VIPER27HD IC which contains:

    It is illegal to decrypt a PSpice model without the consent of the owner.

    Many vendors encrypt their models so that their IP can be protected while allowing the user to run the model in one simulator. Models are usually developed to be run in one simulator primarily.

  2. LMR54410: The Pspice file for this is encrypted and hence it cannot be imported in other softwares. Please let me know from where we can get the decrypted file. which contains:

    Unfortunately, there's no way to import the spice file into other software. I would recommend testing everything you can in PSpice for TI related to LMR54410.

  3. UCC25800-Q1: LT-Spice model for Simulation purpose contains:

    As we do not support LTspice, so we do not know what to do. The PSpice model is only assumed to work with PSpice for TI or a full version of PSpice. We do not help to make it work for other simulation software.

    PSpice for TI is a free download and free for use, so please this software for your simulation. We will support your need if you use this software.

The 3rd thread above suggests TI don't support using the UCC25800 module in LTspice, so your only option appears to use PSpice.

Note: The above conclusion came only from the threads found on the TI forums, and I haven't myself attempted to use the UCC25800 PSpice encrypted model in LTspice. The other answer suggests it should be possible to use an encrypted model in LTspice.


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