Question

What is the impedance from the output port according to Millers Theorem?

(a) Zin2 = Z × K / K – 1

(b) Zin2 = Z × K / K + 1

(c) Zin2 = Z / K – 1

(d) Zin2 = Z / K + 1

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This interesting question is from Frequency Response in division Frequency Response of Electronic Devices & Circuits

Answer 1

Right choice is (a) Zin2 = Z × K / K – 1

Explanation: According to Millers Theorem, to calculate the input impedance from the output port we use: Zin2 = Z × K / K – 1. Where, Z is the original circuit impedance and K is the ratio of the two nodal voltages V2 / V1.