Question

How do we calculate the inverse hybrid parameter g12 of a two – port network?

(a) g12 = I2 / I1

(b) g12 = I1 / I2

(c) g12 = V1 / V2

(d) g12 = V2 / V1

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Question is taken from Measurement of H-Parameters in portion Small-Signal Low-Frequency AC models of Transistors of Electronic Devices & Circuits

Answer 1

Right choice is (b) g12 = I1 / I2

To elaborate: The inverse hybrid parameter g12 for a two – port network is calculated by short circuiting the input terminal. In this case, the current V1 is equal to zero. The parameter g12 is calculated by taking the ratio of input terminal current over output terminal current.