The common base amplifiers usually has（ ）
A. large input impedance and large output impedance.
B. small input impedance and large output impedance.
C. small input impedance and small output impedance.
D. large input impedance and small output impedance.
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In the cascade system, ( )
A. the input impedance depends on the first stage and the output impedance depends on the last stage.
B. the input impedance depends on the first stage and the output impedance depends on the first stage.
C. the input impedance depends on the last stage and the output impedance depends on the last stage.
D. the input impedance depends on the last stage and the output impedance depends on the last stage.
There are three states of operation for the BJT. When it operated in the linear region, it means that ( )
A. the Base–Emitter junction is forward-biased and Base–Collector junction is reverse-biased.
B. the Base–Emitter junction is forward-biased and Base–Collector junction is forward-biased.
C. the Base–Emitter junction is reverse-biased and Base–Collector junction is reverse-biased.
D. the Base–Emitter junction is reverse-biased and Base–Collector junction is forward-biased.
There are three states of operation for the BJT. When it operated in the saturation region, it means that ( )
A. the Base–Emitter junction is forward-biased and Base–Collector junction is reverse-biased.
B. the Base–Emitter junction is forward-biased and Base–Collector junction is forward-biased.
C. the Base–Emitter junction is reverse-biased and Base–Collector junction is reverse-biased.
D. the Base–Emitter junction is reverse-biased and Base–Collector junction is forward-biased.
The common ( ) amplifiers has 180⁰ phase shift between input and output.
A. collector
B. base
C. emitter
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