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This diagram from a lab assignment is not making sense to me...any help would be greatly appreciated.

Diagram

I don't understand what \$I_{C_\max}\cdot R_e\$ is and why it appears on this diagram. Even if it should be on the diagram, why is it only \$R_e \$ and not \$R_{DC}\$? Shouldn't \$V_{CE_\min}\$ be from \$0\mathrm{V}\$ to \$\sim0.3\mathrm{V}\$?

When calculating \$R_e\$ and \$R_c\$, this equation is used Equation I've tried leaving the term I don't understand out (probably a bad idea lol), which causes either \$R_c\$ or \$R_e\$ to be negative and I have tried calling it \$I_{C_\max}\cdot R_{DC}\$, which results in two negative resistances...

Side question: CB Diagram For a Common base amplifier, would \$R_{AC}\$ include \$R_s\$ (the signal resistance)? Thus should be \$R_C\parallel R_L + R_e\parallel R_s\$?

Thanks a ton!

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  • \$\begingroup\$ Look here electronics.stackexchange.com/questions/301617/… and notice how the voltage across RE resistor change with an input signal. \$\endgroup\$ – G36 Mar 9 at 6:11
  • \$\begingroup\$ You are thinking of Vce(sat ) instead of Vce(min for linear operation. THis depends on harmonic distortion spec or variation of sine asymmetry which can easily be 10% when Vce< 1V and at high current <2V . I would choose a number in that preferred linear range depending on Ic/Ic max \$\endgroup\$ – Sunnyskyguy EE75 Mar 9 at 9:02

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