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In introductory texts, the BJT is said to be a unilateral device. I think it means that the base current is only a function of Vbe; and Vbe is not function of Vce and Ic(?) Is the following BJT model unileteral or bileteral?

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In other words, according to the above model, is the base current or Vbe function of any output parameters like Vce or Ic?

pnatk
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  • That's a small-signal version (using derivatives) and is useless for large-scale results. The large-scale models (lacking Early Effect \$r_o\$, though) are [here](https://electronics.stackexchange.com/a/252199/38098). If you focus on active mode and take the deriviative, you'll get the linearized hybrid-\$\pi\$. But it's only valid close-by around a specific operating point. – jonk Mar 02 '20 at 22:03
  • I see but Im asking only about the approximate model in the question. Is that model unileteral? – pnatk Mar 03 '20 at 00:55
  • Well, if I felt I understood the exact question I might try and offer a suggestion. But I don't feel as though I do. So I'm not sure which direction to head. That said, do you understand how a current mirror works? – jonk Mar 03 '20 at 01:45

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