By replacing the transistor in the VBE multiplier by its hybrid-, small-signal model
Chapter 12, Problem 12.31(choose chapter or problem)
By replacing the transistor in the VBE multiplier by its hybrid-, small-signal model (with ro neglected), show that the incremental resistance between the two terminals of the multiplier is given by r = R2 +(R1 r ) 1+gm(R1 r ) Evaluate r for the case R1 = R2 = 1.2 k, with the transistor operating at IC = 1 mA and having = 100.
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