Practice Exam Test Questions
Choose the letter of the best answer in each questions.
1. If an op-amp comparator has a gain of 100,000, an input difference of 0.2 mV above reference, and a supply of ±12 V, the output will be
- A. 20 V.
- B. 12 V.
- C. 10 V.
- D. 15 V.
2. To reduce the effects of noise resulting in erratic switching of output states of a comparator, you can use
- A. the upper trigger point.
- B. the lower trigger point.
- C. nonzero-level detection.
- D. hysteresis.
3. A comparator with a Schmitt trigger has
- A. two trigger levels.
- B. a fast response.
- C. a slow response.
- D. one trigger level.
4. In a comparator with output bounding, what type of diode is used in the feedback loop?
- A. Schottky
- B. junction
- C. zener
- D. varactor
5. In a flash A/D converter, the priority encoder is used to
- A. select the first input.
- B. select the highest value input.
- C. select the lowest value input.
- D. select the last input.
6. A differentiator is used to measure
- A. the sum of the input voltages.
- B. the difference between two voltages.
- C. the area under a curve.
- D. the rate of change of the input voltage.
7. An op-amp has an open-loop gain of 90,000. Vsat = ±13 V. A differential voltage of 0.1 V p-p is applied between the inputs. What is the output voltage?
- A. 13 V
- B. –13 V
- C. 13 Vp-p
- D. 26 Vp-p
8. Refer to Figure 13-1(a). Determine the output voltage.
Figure 13-1
- A. 1 V
- B. –1 V
- C. +Vsat
- D. –Vsat
9. Refer to Figure 13-1(b). What is the output voltage?
- A. 2 V
- B. –2 V
- C. +Vsat
- D. –Vsat
10. Refer to Figure 13-1(c). With the inputs shown, determine the output voltage.
- A. 7 V
- B. –7 V
- C. +Vsat
- D. –Vsat
11. Refer to Figure 13-2(a). What is the output voltage?
Figure 13-2
- A. 0.5 V
- B. –0.5 V
- C. 2 V
- D. –2 V
12. Refer to Figure 13-2(b). Determine the output voltage, VOUT.
- A. 1.05 V
- B. –0.35 V
- C. 0.35 V
- D. –1.05 V
13. Refer to Figure 13-3(a). Determine the upper trigger point.
Figure 13-3
- A. V(out)max
- B. –V(out)max
- C. –1.41 V
- D. +1.41 V
14. Refer to Figure 13-3(b). Determine the lower trigger point.
- A. +V(out)max
- B. –V(out)max
- C. –2.47 V
- D. +2.47 V
15. Refer to Figure 13-4(a). This circuit is known as
Figure 13-4
- A. a noninverting amplifier.
- B. a differentiator.
- C. an integrator.
- D. a summing amplifier.
16. Refer to Figure 13-4(b). This circuit is known as
- A. a noninverting amplifier.
- B. a differentiator.
- C. an integrator.
- D. a summing amplifier.
17. Refer to Figure 13-4(b). A square-wave input is applied to this amplifier. The output voltage is most likely to be
- A. a square wave.
- B. a triangle wave.
- C. a sine wave.
- D. no output.
18. Refer to Figure 13-4(b). If Vin = 5 V, the rate of change of the output voltage in response to a single pulse input is:
- A. 15.2 mV/µs
- B. 1.52 V/µs
- C. 1.52 mV/µs
- D. 15.2 V/µs
19. The output of a Schmitt trigger is a
- A. pulse waveform.
- B. sawtooth waveform.
- C. sinusoidal waveform.
- D. triangle waveform.
20. A Schmitt trigger is
- A. a comparator with only one trigger point.
- B. a comparator with hysteresis.
- C. a comparator with three trigger points.
- D. none of the above.
21. An integrator circuit
- A. uses a resistor in its feedback circuit.
- B. uses an inductor in its feedback circuit.
- C. uses a capacitor in its feedback circuit.
- D. uses a resistor in its feedback circuit or uses a capacitor in its feedback circuit
22. In a(n) _____, when the input voltage exceeds a specified reference voltage, the output changes state.
- A. integrator
- B. differentiator
- C. summing amplifier
- D. comparator
23. A good example of hysteresis is a(n)
- A. AM radio.
- B. thermostat.
- C. alarm clock.
- D. none of the above
24. A comparator with hysteresis is sometimes known as a(n)
- A. integrator.
- B. differentiator.
- C. Schmitt trigger.
- D. none of the above
25. What is (are) the necessary component(s) for the design of a bounded comparator?
- A. rectifier diodes
- B. zener diodes
- C. both of the above
26. Which of the following are variations of the basic summing amplifier?
- A. averaging amplifier
- B. scaling amplifier
- C. both of the above
27. What circuit produces an output that approximates the area under the curve of an input function?
- A. integrator
- B. differentiator
- C. summing amplifier
- D. comparator
28. _____ is a mathematical process for determining the rate of change of a function.
- A. Integration
- B. Differentiation
- C. Summing
- D. Comparatoring
29. A(n) ______ amplifier is a summing amplifier with a closed-loop gain equal to the reciprocal of the number of inputs.
- A. averaging
- B. scaling
- C. differentiating
- D. none of the above
30. What type(s) of circuit(s) use comparators?
- A. summer
- B. nonzero-level detector
- C. averaging amplifier
- D. summer and nonzero-level detector
TRUE/FALSE
1. In an op-amp comparator, when the input voltage exceeds a reference voltage, the voltage output changes state.
- A. True
- B. False
2. Bounding allows the output of a comparator to be an unlimited voltage.
- A. True
- B. False
3. A positive feedback network for hysteresis improves an op-amp comparator's noise immunity.
- A. True
- B. False
4. Operational amplifiers are never used as nonlinear devices.
- A. True
- B. False
5. The output voltage of a summing amplifier is proportional to the sum of the input voltages.
- A. True
- B. False
6. The difference between the UTP and the LTP is the hysteresis voltage.
- A. True
- B. False
7. An op-amp integrator uses a capacitor as the feedback element.
- A. True
- B. False
8. An op-amp can be used as a comparator to determine when an input voltage exceeds a certain level.
- A. True
- B. False
9. The output of an op-amp comparator will be zero when the input voltage exceeds the reference voltage.
- A. True
- B. False
10. The R/2R ladder is commonly used for D/A converters.
- A. True
- B. False
Post a Comment
EmoticonClick to see the code!
To insert emoticon you must added at least one space before the code.