AdvancedA-002-007-010
The FET amplifier common drain circuit is similar to which of the following bipolar transistor amplifier circuits?
B
Answer
Circuit design and power supplies
Type
A
Common mode
B
Common collector
C
Common base
D
Common emitter
Answer Notes
Just as we map FET terminals to BJT terminals for other configurations, the FET's Drain maps directly to the BJT's Collector. Therefore, a "common drain" amplifier is the functional equivalent of a "common collector" amplifier.
Both of these circuits are widely used as buffer amplifiers because they feature a high input impedance and a low output impedance. They are also both known by their "follower" nicknames: the source follower (FET) and the emitter follower (BJT), because their output signals do not invert and closely track their input signals.
The common emitter and common base options are incorrect because they functionally map to the common source and common gate FET configurations, respectively.
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The FET amplifier common source circuit is similar to which of the following bipolar transistor amplifier circuits?
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The FET amplifier common gate circuit is similar to which of the following bipolar transistor amplifier circuits?