LTSpice - How to add new Diode

Discussion in 'Homework Help' started by PsySc0rpi0n, Mar 4, 2014.

  1. PsySc0rpi0n

    Thread Starter Well-Known Member

    Mar 4, 2014
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    Hello everyone...

    Hope I'm creating this thread in the right place...

    I need to add a new Diode to LTSpice to perform some academic simulations but i don't know how to do it.

    Adding just a Spice Directive looks like it's not enough...

    Can anyone help me?

    I have this settings to the Diode 1N4001:

    Code ( (Unknown Language)):
    1.  
    2. .MODEL D1N4001 D IS=29.5E-9 RS=73.5E-3 N=1.96 CJO=34.6P VJ=0.627
    3. +M=0.461 BV=60 IBV=10U
    4.  
     
  2. crutschow

    Expert

    Mar 14, 2008
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    Go to the LTC folder (possibly in the Program Files (x86) folder) and then to LTC\LTspiceIV\lib\cmp.

    Make a backup copy of "standard.dio" in case you goof. (You can label it standarddio.bu for example).

    Open "standard.dio" in wordpad (not Word). Add in your 1N4001 model information to that file.

    Save the file as a standard text file.

    Now when you close and reopen LTspice, D1N4001 should be there when you open the diode selection box for any diode in your schematic.
     
  3. PsySc0rpi0n

    Thread Starter Well-Known Member

    Mar 4, 2014
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    But should i use that ".MODEL D1N4001 ..." directive anywhere in LTSpice?

    I'm using Linux. Can i do that with vim?
     
  4. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    hi Pysi',

    The attached txt file is my copy of the standard.dio [ change the .txt back to .dio] , its got the 1N400x series diode models and many others.

    Make a backup copy of your existing standard.dio , then move the file I have attached to the LTS/Lib/Cmp Folder.

    E
     
  5. PsySc0rpi0n

    Thread Starter Well-Known Member

    Mar 4, 2014
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    Ok, thank you!

    Later today I'll do it.

    I have a report to do for my Electronics classes and i need to work out some simulations of that diode!
     
  6. PsySc0rpi0n

    Thread Starter Well-Known Member

    Mar 4, 2014
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    One other question, please!

    Whats the difference between the caracteristics of your 1N4001 diode to that one I've posted in my first post???? I can see there are some diferente values!
     
  7. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    Get the datasheet for the manufacturer of the type you need to simulate then edit the parameters for the 1N4001 in the standard.dio file.

    The d/s specifications do tend to be different from some manufacturers.

    E

    EDIT:
    List of manufacturers
    http://www.datasheetcatalog.com/datasheets_pdf/1/N/4/0/1N4001.shtml
     
    Last edited: Mar 5, 2014
  8. PsySc0rpi0n

    Thread Starter Well-Known Member

    Mar 4, 2014
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    Ok, thank you for replying...

    I'm trying to simulate the diode on a resistive circuit only for academic purposes but looks like i'm not getting any diferences between using the directives or using nothing.

    Please check this screen of what I'm trying to do.

    And the file 1N4011.sp3 has the following inside:

    Code ( (Unknown Language)):
    1.  
    2. .MODEL 1N4001 D(IS=2.55E-9 RS=0.042 N=1.75 TT=5.76E-6 CJO=1.85E-11 VJ=0.75 M=0.333 BV=50 IBV=1E-5 )
    3.  
     
  9. Jony130

    AAC Fanatic!

    Feb 17, 2009
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    Check this simulation file
     
  10. PsySc0rpi0n

    Thread Starter Well-Known Member

    Mar 4, 2014
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    Ok, how do i use that file? Sorry, i'm just starting with LTSpice!
     
  11. Jony130

    AAC Fanatic!

    Feb 17, 2009
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    Simply change Draft199.asc.txt into Draft199.asc
     
  12. PsySc0rpi0n

    Thread Starter Well-Known Member

    Mar 4, 2014
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    Ok i have opened the file but LTSpice doesn't let me measure voltages in the parallel of resistors and diodes... It only alloes me to measure currents...
     
  13. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    hi,
    This plot shows the Vdiodes

    Is this what you are asking.?

    E
     
  14. Jony130

    AAC Fanatic!

    Feb 17, 2009
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    Open this file in LTspice next run the simulation and after you see the plot simply point and click at a wire to plot the voltage on that wire.
     
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  15. PsySc0rpi0n

    Thread Starter Well-Known Member

    Mar 4, 2014
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    I got it , i got it...

    But i still have a question...

    In plot that Jony130 sent me, we have a parallel of 2 R and 2 D , right?

    One D has no specifications, and the other has.

    What is that LTSpice sees at that diode with no specification?



    PS:
    And how do i change the scales? From Volts to Amps, for instance? In Jony130 ploti have Amps in Y-axis and Volts in X-axis...
     
  16. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    Hi,
    Left Click Help/Help Topics

    Type the letter 'D' in the Keyword to find.

    Left click 'List' button

    Then from the drop list double left click 'D. Diode'

    OK.
     
    Last edited: Mar 5, 2014
  17. crutschow

    Expert

    Mar 14, 2008
    13,014
    3,234
    Here's a update of Eric's file. I added the 1N4000X voltage ratings and the Zener voltages so they would show on the diode listing in LTspice. Just delete the .txt at the end of the file name.

    View attachment standard.dio.txt
     
  18. anhnha

    Active Member

    Apr 19, 2012
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    Is it possible to subtract two curves in LTspice?
     
  19. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    hi,
    Yes,
    It would be best if you create your own thread for this topic.

    E
     
  20. PsySc0rpi0n

    Thread Starter Well-Known Member

    Mar 4, 2014
    1,184
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    Is 1N4001X different than 1N4001??? I can't find it in your file!

    Thanks
     
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