Analog Electronics

If it is desired to have low output impedance in an amplifier circuit then we should use

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Question: If it is desired to have low output impedance in an amplifier circuit then we should use
[A].

common collector circuit

[B].

common base circuit

[C].

common emitter circuit

[D].

either (b) or (c)

Answer: Option A

Explanation:

Therefore CC configuration is used for impedance matching.

In all base driver amplifiers__________?

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In all base driver amplifiers__________?

A. ac collector voltage is 180° out of phase with ac base voltage
B. ac emitter voltage is 180° out of phase with ac base voltage
C. ac collector voltage is in phase with ac base voltage
D. none of the above

Three identical amplifiers with each one having a voltage gain of 50,input resistance of 1KΩ & output resistance of 250 ,are cascaded.The open circuit voltage gain of combined amplifier is_________?

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Three identical amplifiers with each one having a voltage gain of 50,input resistance of 1KΩ & output resistance of 250 ,are cascaded.The open circuit voltage gain of combined amplifier is_________?

A. 49dB
B. 51dB
C. 98dB
D. 102dB

An amplifier using an opamp with slew rate SR=1v/µsec has a gain of 40db.if this amplifier has to faithfully amplify sinusoidal signals from dc to 20 KHz without introducing any slew-rate induced distortion, then the input signal level must not exceed________?

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An amplifier using an opamp with slew rate SR=1v/µsec has a gain of 40db.if this amplifier has to faithfully amplify sinusoidal signals from dc to 20 KHz without introducing any slew-rate induced distortion, then the input signal level must not exceed________?

A. 795mV
B. 395mV
C. 795 mV
D. 39.5mV

An npn BJT has gm=38mA/v, cµ =10¯14 F, cπ =10¯13F and DC current gain β0=90.For this transistor fT & fβ are________?

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An npn BJT has gm=38mA/v, cµ =10¯14 F, cπ =10¯13F and DC current gain β0=90.For this transistor fT & fβ are________?

A. fT =1.64 x 108 Hz & fβ = 1.47 x 1010 Hz.
B. fT =1.47 x 1010 Hz & fβ = 1.64 x 108 Hz
C. fT =1.33 x 1012 Hz & fβ = 1.47 x 1010 Hz
D. fT =1.47 x 1010 Hz & fβ = 1.33 x 1012 Hz