LTSPICE IV - model not including

Discussion in 'Electronics Resources' started by Skeebopstop, Mar 25, 2009.

  1. Skeebopstop

    Thread Starter Active Member

    Jan 9, 2009
    358
    3
    Hi all,

    I have attached a model I am trying to include in LTSPICE IV. I have placed it in the lib, lib/sym, lib/cmp and lib/sub folders just to make sure it would find it.

    I use the .inc MMSZ4678T1G.LIB (attachement is suitably renamed to .txt for allowing to upload) directive, than use CTRL+right click on a 'zener' symbole to update its value field to be mmsz4678t1g.

    Whenever I try to simulate it says it can't locate the model.

    Any help?
     
  2. Ron H

    AAC Fanatic!

    Apr 14, 2005
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    OK, I got it to work this way:
    1. Save the subckt file in the SUB folder as mmsz4678t1g.sub.
    2. Place a zener symbol on the schematic.
    3. Place a .op(tion) .lib mmsz4678t1g.sub to call the subcircuit file.
    4. Right-click on the symbol's "D" and change it to mmsz4678t1g.
    5. This is the key: You have to change the symbol instance from D to X, since you have a .subckt instead of a .model. Do this by ctrl-rightclicking on the symbol and changing the Prefix from D to X. You can read about this in Help by searching for "third-party".

    I ran a simple sim and verified that it was a 1.8V@50uA zener.

    See attachments. If you want to run my sim, you can import the .asc file into your directory where your simulations are stored. You will have to reopen SWcad after you save the file.
     
  3. Skeebopstop

    Thread Starter Active Member

    Jan 9, 2009
    358
    3
    Thanks, it was definetely the X part that was eluding me!
     
  4. Ron H

    AAC Fanatic!

    Apr 14, 2005
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    657
    I'm glad I could help.
     
  5. loosewire

    AAC Fanatic!

    Apr 25, 2008
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    Was that about testing a curcuit with software ?
     
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