I mean the normal working modes (cutoff, forward/reverse active, saturation).
Or an other form of the question: Do Ebers-Moll cover the whole working domain of BJT (in potential and current values)?
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\$\begingroup\$ No, it doesn't. \$\endgroup\$– Andy akaCommented Oct 25, 2020 at 16:32
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\$\begingroup\$ The model does not take into account the inner capacities, high frequency effects, heat dependency. Besides these covers all modes? \$\endgroup\$– RobertSziliCommented Oct 25, 2020 at 16:40
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1\$\begingroup\$ Remember this: "All models are wrong, some models are useful". It depends on what mode the transistor is in and how you want to use it if a model will give a result that can be relied upon. Also: if some model covers "everything", then why do other models exist? \$\endgroup\$– BimpelrekkieCommented Oct 25, 2020 at 16:57
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2\$\begingroup\$ Yes it does cover the four working areas you mention in DC quasi-static operations. The alphas (forward and reverse) and the saturation currents dependencies are somehow hidden, you should have a function of Ic,Vcb,temp etc. describing them. \$\endgroup\$– carlocCommented Oct 25, 2020 at 17:43
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2\$\begingroup\$ The Ebers-Moll "model" comes in three flavors (prior to Gummel-Poon arriving.) I discuss the level-1 model here. This does NOT include bulk resistance, charge storage (which are in the level 2 model), or bandwidth modulation (which appears in the level 3 model.) Gummel-Poon takes a more physically-aligned approach for bandwidth modulation and includes the so-called Late Effect, when it does so. All of these models work in all quadrants. (These are the full non-linear models and are not some simplified, "linearized" small-signal model.) \$\endgroup\$– jonkCommented Oct 25, 2020 at 18:14
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From the comments and some research: Ebers-Moll is quite accurate approximation of a BJT's low frequency processes. It does not deal with delay effects coming from inner capacities. But for a low freq textbook circuit describes well the four states mentioned above.