Electronics-Operational Amplifiers

Electronics-Operational Amplifiers
21. In an open-loop op-amp circuit, whenever the inverting input (–) is negative relative to the noninverting input (+), the output will:
  • swing negative
  • close the loop
  • be balanced
  • swing positive
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22. With a differential gain of 50,000 and a common-mode gain of 2, what is the common-mode rejection ratio?
  • –87.9 dB
  • –43.9 dB
  • 43.9 dB
  • 87.9 dB
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23. If the input to a comparator is a sine wave, the output is a:
  • ramp voltage
  • sine wave
  • rectangular wave
  • sawtooth wave
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24. What three subcircuits does a phase locked loop (PLL) consist of?
  • phase comparator, comparator, and VCO
  • phase comparator, bandpass filter, and VCO
  • phase comparator, bandpass filter, and demodulator
  • phase comparator, low-pass filter, and VCO
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25. The major difference between ground and virtual ground is that virtual ground is only a:
  • voltage reference
  • current reference
  • power reference
  • difference reference
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26. If an op-amp has one input grounded and the other input has a signal feed to it, then it is operating as what?
  • Common-mode
  • Single-ended
  • Double-ended
  • Noninverting mode
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27. If the feedback/input resistor ratio of a feedback amplifier is 4.6 with 1.7 V applied to the noninverting input, what is the output voltage value?
  • 7.82 V
  • saturation
  • cutoff
  • 9.52 V
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28. The Schmitt trigger is a two-state device that is used for:
  • pulse shaping
  • peak detection
  • input noise rejection
  • filtering
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29. When a capacitor is used in place of a resistor in an op-amp network, its placement determines:
  • open- or closed-loop gain
  • integration or differentiation
  • saturation or cutoff
  • addition or subtraction
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30. How many logic states does an S-R flip-flop have?
  • 2
  • 3
  • 4
  • 5
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