Find the common base configuration current gain of a transistor, if the common emitter configuration current gain of the transistor is 50.

Question

Question

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SSC JE Electrical 10 Oct 2023 Shift 2 Official Paper-I

Answer 1

Current gains of Bipolar Junction Transistor

1.) Common base current gain: It is the ratio of the collector current to the emitter current.

\(α={I_C\over I_E}\)

2.) Common emitter current gain: It is the ratio of the collector current to the base current.

\(β={I_C\over I_B}\)

3.) Common collector current gain: It is the ratio of the emitter current to the base current.

\(γ={I_E\over I_B}\)

Relationship between α, β and γ:

\(α={β\over 1+β}\)

\(\gamma=β+1\)

Calculation

Given, β = 50

\(α={50\over 1+50}\)

α = 0.98