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How to model this BZX79C6V2 zener diode in spice(ltspice recommended )?

enter image description here reference:-https://www.farnell.com/datasheets/2303921.pdf These are the possible parameters https://ltwiki.org/LTspiceHelp/LTspiceHelp/D_Diode.html

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  • \$\begingroup\$ Star Lord - Hi, Please note the site rule which requires that when a post includes content (e.g. text, image, photo etc.) copied or adapted from elsewhere, that content must be correctly referenced. As a minimum, for online material, the source webpage or PDF etc. should be linked (see that rule regarding references for books / articles etc.). Therefore please edit your question to include the original source link for that image (and please remember it's your responsibility to do that in future). Thanks. (Please see the tour & help center if you haven't reviewed them yet.) \$\endgroup\$
    – SamGibson
    Commented Oct 1, 2023 at 21:28
  • \$\begingroup\$ Making a SPICE model for a component usually requires, at a minimum, a few dozen of the component (including some from at least a few different lots), a curve tracer, and a lot of time. It's not something you can just do from the datasheet. \$\endgroup\$
    – Hearth
    Commented Oct 1, 2023 at 22:58

1 Answer 1

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Spice models are like alchemy, you have to be some kind of mad scientist to figure them out. Okay, that may be an exaggeration, but with just the data sheet you won't be able to get a lot of the parameters.

The easiest thing to do is find an existing model. A lot of models can be found just by doing an internet search, for example I found this one for the device in question.

.MODEL BZX79C6V2 D(IS=2.4710E-9 N=2.0880 RS=1.0000E-3 IKF=5.900 CJO=95.650E-12 M=.3487 VJ=.7022 ISR=10.010E-21 BV=6.50 IBV=.8623 TT=140E-9 Vpk=6.2 mfg=NXP type=zener)

You can see the the datasheet wouldn't be much help coming up with that. Usually the manufacturers supply the models, as they have a much more intimate knowledge of the device than anyone else.

If you can't find a model you can look for one that's close, maybe the same series but with a different Zener voltage, then just changing BV will probably be good enough for most uses.

To use the model copy and paste it as a spice directive on your schematic, then add a generic Zener, Ctrl+Right click on it and change the value from D to whatever the name of the model is, in this case BZX79C6V2.

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    \$\begingroup\$ There isn't any need to change Vpk unless you're putting it into your LTspice library; Vpk is purely a "tag" field, with no impact on the simulation at all. \$\endgroup\$
    – Hearth
    Commented Oct 1, 2023 at 22:59
  • \$\begingroup\$ @Hearth Removed it. \$\endgroup\$
    – GodJihyo
    Commented Oct 2, 2023 at 4:25
  • \$\begingroup\$ @GodJihyo How did you find spice model for this ? i couldn't find it in internet \$\endgroup\$
    – Star Lord
    Commented Oct 2, 2023 at 5:09
  • \$\begingroup\$ @StarLord You just have to try different queries, sometimes you have to put the part number in quotes, sometimes add ltspice or spice to the search terms, and which search engine you use makes a difference. \$\endgroup\$
    – GodJihyo
    Commented Oct 2, 2023 at 5:43

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