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Sarkari MCQs Government Exam Question Bank
Question no. 25313

For what primary purpose is an emitter follower utilized________________?

Select your answer for: For what primary purpose is an emitter follower utilized________________?
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Answer: B. Impedance matching

Explanation

Emitter followers feature high input impedance and low output impedance characteristics. Transforming high source resistance to low load resistance achieves optimal impedance matching. Impedance matching prevents signal loss between mismatched electronic circuit stages. The emitter follower is a common-collector BJT amplifier configuration with unity voltage gain. Impedance matching maximizes power transfer and signal integrity between cascaded stages. Buffer amplifiers isolate sensitive preceding stages from heavy loads downstream.

Audio mixing consoles use emitter followers as buffer stages between different equipment. Measuring instruments incorporate high input impedance buffers to prevent loading test circuits. Signal generators rely on output matching stages to drive fifty-ohm transmission cables. Current gain is a feature, but impedance matching is the primary systemic purpose. Voltage gain is actually slightly less than unity in emitter follower circuits. None of the above is wrong because impedance matching correctly identifies its primary role.

Subject
Engineering
Category
Electrical Engineering
Topic
—
Difficulty
medium

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