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There're a lot of field we need to fill in when create a custom model, however I often cannot find the information in business product datasheet.

For example, here's 2SC5198 BJT from Toshiba: http://www.toshiba.com/taec/components2/Datasheet_Sync/201011/DST_2SC5198-TDE_EN_7886.pdf

Could anyone help me transform this datasheet in to a circuitlab BJT model?

please help!

@alstontsao,

Welcome to CL.

Unfortunately you cannot map datasheet parameters directly into device models.

About datasheet, device and simulation model parameters

To edit models see:

https://www.circuitlab.com/docs/faq/#q_add_custom_models

https://www.circuitlab.com/forums/modeling-and-simulation/topic/sq59q7zy/model-a-low-leakage-schottky-diode/

As I said above, you cannot simply map datasheet parameters onto a device simulation model.

However, if you can find a spice model for your target device, then you can edit the relevant parameters of one of the built-in CL models and use that in your circuit.

Sadly it doesn't look as though Toshiba supply a model for the 2SC5198.

You may find one floating around the web that has been liberated from a PSpice or similar library but check it is from a reputable source and not just a renamed copy of some generic device model.

And please respect any copyright on it.

For more information please see this thread:

https://www.circuitlab.com/forums/basic-electronics/topic/9dg62j8d/help-for-beginners-hobbyists/

Note that there are some unanswered questions about editing CL model parameters (which may not affect you anyway):

https://www.circuitlab.com/forums/feature-requests/topic/6k7v65fx/questions-about-editing-model-parameters/

This thread has several links to more about spice diode parameters:

https://www.circuitlab.com/forums/modeling-and-simulation/topic/4jex93sw/importing-transistor-from-datasheet/#comment_2309

SPICE parameters for devices have little to do with datasheet specifications. They are much more to do with semiconductor physics and the particular process under which a given device is manufactured at the foundry.

Consequently it is not always a simple task to map datasheet information onto the model parameters.

If you want to try to understand more about what the SPICE - and hence CL - parameters mean in diodes, bipolar transistors and MOSFETs, then you might like to have a look at:

http://www3.imperial.ac.uk/pls/portallive/docs/1/56133736.PDF

with individual slide sets:

http://www3.imperial.ac.uk/pls/portallive/docs/1/7292571.PDF

http://www3.imperial.ac.uk/pls/portallive/docs/1/7292572.PDF

http://www3.imperial.ac.uk/pls/portallive/docs/1/7292573.PDF

For more detailed information about bjt's in particular, have a look at this book:

http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=01480193

available from:

http://www.lulu.com/spotlight/iangetreu

and

http://www.amazon.com/Modeling-Bipolar-Transistor-Ian-Getreu/dp/B000EYPQLU

Another excellent (and free) book about transistor modelling, go to:

http://www.aeng.com/spice_modeling.htm

and register to get a copy of:

Definitive Handbook of Transistor Modeling