Electronic Devices-Operational Amplifiers

Electronic Devices-Operational Amplifiers
1. For an op-amp having a slew rate SR = 5 V/ms, what is the maximum closed-loop voltage gain that can be used when the input signal varies by 0.2 V in 10 ms?
  • 150
  • 200
  • 250
  • 300
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2. An op-amp has an open-loop gain of 100,000 and a cutoff frequency of 40 Hz. Find the open-loop gain at a frequency of 30 Hz.
  • 800
  • 8,000
  • 80,000
  • 100,000
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3. What is the level of the voltage between the input terminals of an op-amp?
  • Virtually zero
  • 5 V
  • 18 V
  • 22 V
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4. An op-amp has an open-loop gain of 75,000 and a cutoff frequency of 100 Hz. At 1 kHz the open-loop gain is down by
  • 10 dB.
  • 6 dB.
  • 20 dB.
  • 3 dB.
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5. What is the difference output voltage of any signals applied to the input terminals?
  • The differential gain times the difference input voltage.
  • The common-mode gain times the common input voltage.
  • The sum of the differential gain times the difference input voltage and the common-mode gain times the common input voltage.
  • The difference of the differential gain times the difference input voltage and the common-mode gain times the common input voltage.
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6. A three-stage op-amp can have a maximum phase lag of ________°.
  • –180
  • –90
  • –270
  • none of the above
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7. The summing amplifier contains an inverting amplifier.
  • TRUE
  • FALSE
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8. What is the open-loop gain of an op-amp at the gain-bandwidth product of the op-amp?
  • 200,000
  • 50,000
  • 200
  • 1
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9. The ________ amplifier configuration has the highest input impedance and the lowest output impedance of the three basic op-amp configurations.
  • non-inverting
  • inverting
  • voltage-follower
  • [NIL]
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10. A certain op-amp has an open-loop voltage gain of 150,000. What is this gain expressed in dB?
  • 51.7 dB
  • 103.5 dB
  • 150,000 dB
  • 5.18 dB
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