Electronic Devices-BJIt Amplifiers

Electronic Devices-BJIt Amplifiers
21. When the bypass capacitor is removed from a common-emitter amplifier, the voltage gain
  • increases.
  • decreases.
  • has very little effect.
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22. In a common-base amplifier, the input signal is connected to the
  • base.
  • collector.
  • emitter.
  • output.
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23. Which of the following is (are) true to achieve a good overall voltage gain for the circuit?
  • The effect of Rs and RL must be considered as a product.
  • The effect of Rs and RL must be considered as a product and evaluated individually.
  • The effect of Rs and RL must be evaluated individually.
  • None of the above
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24. To analyze the common-emitter amplifier, what must be done to determine the dc equivalent circuit?
  • leave circuit unchanged
  • replace coupling and bypass capacitors with opens
  • replace coupling and bypass capacitors with shorts
  • replace VCC with ground
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25. For the common-emitter amplifier ac equivalent circuit, all capacitors are
  • effectively shorts.
  • effectively open circuits.
  • not connected to ground.
  • connected to ground.
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26. Which of the following define(s) the conversion efficiency?
  • Ac power to the load/ac input power
  • Ac power to the load/dc power supplied
  • Dc output power/ac input power
  • All of the above
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27. Which of the following should be done to obtain the ac equivalent of a network?
  • Set all dc sources to zero
  • Replace all capacitors by a short-circuit equivalent.
  • Remove all elements bypassed by the short-circuit equivalent.
  • All of the above
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28. For the collector dc feedback configuration, there is a ________ phase shift between the input and output signals.
  • 45º
  • 90º
  • 180º
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29. The total gain of a multistage amplifier is the ________.
  • sum of individual voltage gains
  • sum of dB voltage gains
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30. Which of the following configurations has an output impedance Zo equal to RC?
  • Fixed-bias common-emitter
  • Common-emitter voltage-divider with bypass capacitor
  • Common-emitter voltage-divider without bypass capacitor
  • All of the above
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