logo

CuriousTab

CuriousTab

Discussion


Home Digital Electronics Digital Design Comments

  • Question
  • The purpose of a pull-up resistor is to keep a terminal at a ________ level when it would normally be at a ________ level.


  • Options
  • A. LOW, float
  • B. HIGH, float
  • C. clock, float
  • D. pulsed, float

  • Correct Answer
  • HIGH, float 


  • Digital Design problems


    Search Results


    • 1. Decoupling capacitors should be tied from VCC on one device to ground on a different device.

    • Options
    • A. True
    • B. False
    • Discuss
    • 2. Is the propagation delay from the clock to the output for the 7476 the same as the delay from the set or reset to the output?

    • Options
    • A. yes
    • B. no
    • Discuss
    • 3. Which of the following circuit parameters would be most likely to limit the maximum operating frequency of a flip-flop?

    • Options
    • A. setup and hold time
    • B. clock pulse HIGH and LOW time
    • C. propagation delay time
    • D. clock transition time
    • Discuss
    • 4. What is the difference between setup time and hold time?

    • Options
    • A. Setup time occurs after the active clock edge, hold time occurs before the active clock edge.
    • B. Setup time occurs before the active clock edge, hold time occurs after the active clock edge.
    • C. Setup time and hold time both occur at the active clock edge.
    • Discuss
    • 5. A settable flip-flop's normal starting state when power is first applied to a circuit is always the ________ state.

    • Options
    • A. reset
    • B. set
    • C. toggle
    • D. dual
    • Discuss
    • 6. Why does the data sheet for the 7476 only give a minimum value for the clock pulse width (both HIGH and LOW)?

    • Options
    • A. nominal value
    • B. best-case condition
    • C. worst-case condition
    • Discuss
    • 7. A Schmitt trigger:

    • Options
    • A. has two trip points
    • B. is a zero crossing detector
    • C. has positive feedback
    • D. has two trip points and positive feedback
    • Discuss
    • 8. A Schmitt trigger has VT+ = 2.0 V and VT? = 1.2 V. What is the hysteresis voltage of the Schmitt trigger?

    • Options
    • A. 0.4 volt
    • B. 0.6 volt
    • C. 0.8 volt
    • D. 1.2 volts
    • Discuss
    • 9. Why should a LED be pulled LOW from a logic gate rather than pulled HIGH?

    • Options
    • A. LOW-level current is smaller.
    • B. LOW-level current is larger.
    • C. HIGH-level current is larger.
    • D. LOW-level current is smaller and HIGH-level current is larger.
    • Discuss
    • 10. Define a race condition for a flip-flop.

    • Options
    • A. The inputs to a trigger device are changing slightly before the active trigger edge.
    • B. The inputs to a trigger device are changing slightly after the active trigger edge.
    • C. The inputs to a trigger device are changing at the same time as the active trigger edge.
    • Discuss


    Comments

    There are no comments.

Enter a new Comment