AWR Design Environment

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Greetings. The figure shows the simulation results of a diode (SDIODE) and a bipolar transistor(GBJT). At the bipolar transistor, the collector base is closed. Why does the diode have a storage phase, but does the bipolar transistor not? This is the same pn transition. Thank you for attention.

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Message 1 of 7

I cannot answer this question without looking at the models.  Please ZIP your project and post it.

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Message 2 of 7

schema file

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Message 3 of 7

As you can see from the simulation results, the two devices behave very similarly, but they are not exactly the same.  The underlying equivalent circuits are different, so they do not behave identically.  The transistor model is on the left (with the "S" terminal tied to the "E" terminal), and the diode model is on the right.  Both of these equivalent circuits are from our documentation (select an element in the schematic and hit F1 to open the help page).  Given the large differences in the actual parameter lists, I do not believe it is valid to compare them at this level.


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Message 4 of 7

What part of the model GBJT then affects the flatter on a flat top? Physically, the closure of the base and collector makes the base-emitter junction of the bipolar transistor a classic pn junction as in a diode.

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Message 5 of 7

This forum is designed to answer questions about how to use our software, and your question is far beyond that area.  As indicated yesterday, the models are quite different (and, importantly, they are models, not physical representations) and they give slightly different results when one model is applied in a manner that is not its primary application.  For more information, I suggest you study the references at the bottom of the help page for each of the models in question.  One thing that may help your research is the fact that both models share the same primary reference (Antognetti and Massobrio).

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Message 6 of 7

Double-click the BJT, click "2nd" button to see secondary parameters, and make TF parameter of BJT same as TT parameter of diode.

Knowing the meaning of the model parameters helps.  Please study the reference.

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Message 7 of 7