• State TI Thinks Resolved
  • Locked Locked
  • Replies 14 replies
  • Answers 1 answer
  • Subscribers 38 subscribers
  • Views 2024 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TINA/Spice/THS3491: Error caused by incompatibility between THS3491 device model and Tina macro-model extraction

steve smith17
Intellectual 510 points
Part Number: THS3491
Other Parts Discussed in Thread: TINA-TI, , LMH5401

Tool/software: TINA-TI or Spice Models

This is a software bug - probably in Tina. I follow your instructions and correctly extract a THS3491 Spice file from the Tina Macro-model. However the spice model is broken and does not work like an op-amp. If I set it for gain of +2 with a 1 Volt input and bipolar +/-15V the simulation tells me the output is 15 Gigavolts. If I make it a unipolar design then it gives me a 7.5V DC output voltage with spikes corresponding to the input pulse edges. To prove that it was Tina and not me doing something wrong I repeated the process for a different device macro-model and it worked perfectly ! Can you please address this promtly because I cannot simulate this part for my new design without a working P-Spice model. Thanks Steve

  • 0
    TI__Genius 9775 points
    Hi Steve,

    FYI, one of our team member we'll take a look at this.

    Herman
  • 0 in reply to Herman Theodorus
    Intellectual 510 points

    Thanks Herman, probably you will be able to reproduce the bug pretty easily, but if not let me know and I can send you my simulation files etc. Steve

  • 0 in reply to steve smith17
    TI__Mastermind 37605 points

    Steve,

    I am a modeling engineer  in the same team as Herman, and want to make sure I understand what you are seeing with the THS3491 model.

    Are you seeing the problem while using the THS3491 model in TINA, or extracting the THS3491 model netlist for use in another simulator?

    If you are seeing the problems while using the model in TINA, would you please upload your test circuit to this thread?

    Regards,
    John

  • 0 in reply to John Miller - Sensing
    Intellectual 510 points
    Hi John, the THS3491 model works just fine in Tina. What I'm doing is extracting the PSpice macromodel by right cicking on the part in Tina then saving as a Pspice model per your instructional video. If I do this for the LMH5401 per your video and run in PSpice it works fine, IF however I do the same for the THS3491 the model gets broken during the conversion process causing the symptoms described earlier. Steve
  • 0 in reply to steve smith17
    Intellectual 510 points

    Hi John, I was wondering if you have been able to successfully reproduce the simulation issue that I've been describing ? If not I do have spice files that I could let you have if you can supply your direct email.

  • 0 in reply to steve smith17
    TI__Genius 9775 points
    Hi Steve (and John),

    I would recommend not to put your work email on E2E post. You can use E2E Direct/Private messaging system. Click on John's E2E link profile, then on the upper right hand corner there is a link "+Connect", then John should be able to accept your "Connect/Friend" request. From there you can exchange conversation through E2E Private Messaging/Inbox.

    Herman
  • 0 in reply to steve smith17
    TI__Mastermind 37605 points

    Steve,

    I will have some feedback by COB tomorrow, 12/12.

    John

  • 0 in reply to John Miller - Sensing
    TI__Mastermind 37605 points
    Steve,
    Which TINA model did you use? The DDA model or the RGT model?
    John
  • 0 in reply to John Miller - Sensing
    Intellectual 510 points

    Hi John, I tried both, same result. But more specifically I used the reference design as suggested in the TI video then right clicked on the part itself to extract the macro model, then saved as spice file. Here's the link:-. THS3491DDA TINA-TI Reference Design (Rev. A)

    Best regards,

    Steve

  • 0 in reply to steve smith17
    TI__Mastermind 37605 points

    Steve,

    I tried the steps given in the training video for the DDA and RGT models and had no problems. I am using Cadence Capture v16.2 with Pspice.
    These models were actually created in Pspice and ported into TINA to create those models.

    One thing  I noticed was that when using the File/Save as command in the TINA netlist viewer, the default model file name is the same as the larger reference circuit, not the actual device model you are seeing in the viewer. For these two it was SBOMAI4A & SBOMAN3 with .CIR extensions.

    Not knowing if you changed the file names before saving them, I left them unchanged, anticipating this might be the problem in Pspice.

    Silly me.

    After generating the symbols (.OLB files) and adding them to the library with the SBOMANx names, they could be placed in a schematic with the proper device names appearing (e.g. THS3491DDA/RGT).

    The test circuits w/models ran and gave the expected results for AC and TRAN sims.
    They are attached to this thread.

    Please give the models and sims a try and let me know if you have any questions or comments.

    Regards,
    John

    THS3491_Pspice.zip

  • 0 in reply to John Miller - Sensing
    Intellectual 510 points
    Thanks John, we are using LTSpice so just need a .CIR or .SUB subcircuit file. I tried extracting file SBOMAN4.CIR but unfortunately this still doesn't work. Simulation runs but results are small spikes (like input is capacitively coupled). I did try to attach the files but your system won't allow me to upload files .ASC, .NET etc.
  • 0 in reply to steve smith17
    Intellectual 510 points
    If you can either try simulating your spice model SBOMAN4.CIR with LTSpice, come up with a viable alternative to generate a subcircuit, or I can send you a copy of my files if you can provide me with a method of doing this that will work for you
  • 0 in reply to steve smith17
    TI__Mastermind 37605 points

    Steve,

    Unfortunately the LTspice EULA forbids us from providing any assistance with that tool, including the use our models.

    John

  • 0 in reply to John Miller - Sensing
    TI__Genius 9775 points
    Hi Steve,

    Since this post has become redundant with your other post: e2e.ti.com/.../2800387, I am going to close/resolve this post.

    The resolve or "TI thinks resolved"/close on this post does not mean we have resolved your issue per se. We just want to consolidate this post with the other post so that we can focus on responding to you through the other post.

    Herman