logo

CuriousTab

CuriousTab

Discussion

Home ‣ Digital Electronics ‣ Interfacing to the Analog World See What Others Are Saying!
  • Question

  • Which of the following describes the basic operation of a single-slope A/D converter.


  • Options
  • A. The input voltage is used to set the frequency of a voltage-controlled oscillator (VCO). The VCO quits changing frequency when the input voltage stabilizes. The frequency of the VCO, which is proportional to the analog input voltage, is measured and is displayed on the digital display as a voltage reading.
  • B. A ramp generator is used to enable a counter through a comparator. When the ramp voltage equals the input voltage the counter is latched and then reset. The counter reading is proportional to the input voltage since the ramp is changing at a constant V/second rate.
  • C. A ramp voltage and analog input voltage are applied to a comparator. As the input voltage causes the integrating capacitor to charge, it will at some point equal the ramp voltage. The ramp voltage is measured and displayed on the digital panel meter.
  • D. Any of the above could be correct, depending on the specific type of A/D converter involved.

  • Correct Answer
  • A ramp generator is used to enable a counter through a comparator. When the ramp voltage equals the input voltage the counter is latched and then reset. The counter reading is proportional to the input voltage since the ramp is changing at a constant V/second rate. 

    • More questions

    • 1. The concurrent section of the hardware description is where the ________ are interconnected.

    • Options
    • A. functions
    • B. components
    • C. circuits
    • D. macrofunctions
      • Discuss
    • 2. Output 6 of a 74138 octal decoder is selected when it is enabled by a data input of:

      A0 = 1
      A1 = 1
      A2 = 0


    • Options
    • A. True
    • B. False
      • Discuss
    • 3. Assume a ROM to be tested is compared with a known good ROM. If the checksums differ, the ROM is ________.

    • Options
    • A. very likely to be good
    • B. definitely good
    • C. very likely to be bad
    • D. definitely bad
      • Discuss
    • 4. The most common TTL series ICs are:

    • Options
    • A. E-MOSFET
    • B. 7400
    • C. quad
    • D. AC00
      • Discuss
    • 5. Microcontrollers often have:

    • Options
    • A. CPUs
    • B. RAM
    • C. ROM
    • D. all of the above
      • Discuss
    • 6. Before an SOP implementation, the expression would require a total of how many gates?

    • Options
    • A. 1
    • B. 2
    • C. 4
    • D. 5
      • Discuss
    • 7. The outputs of a 7485 four-bit magnitude comparator when the inputs are A = 0110 and B = 1010 are:

      A < B is 1
      A = B is 0
      A > B is 1


    • Options
    • A. True
    • B. False
      • Discuss
    • 8. How many outputs are on a BCD decoder?

    • Options
    • A. 4
    • B. 16
    • C. 8
    • D. 10
      • Discuss
    • 9. The GAL16V8 has eight dedicated input pins.

    • Options
    • A. True
    • B. False
      • Discuss
    • 10. The Boolean expression AB + CD is an example of ________.

    • Options
    • A. PAL
    • B. GAL
    • C. SOP
    • D. POS
      • Discuss

    Comments

    There are no comments.
Enter a new Comment




Aptitude

Engineering

Programming

Reasoning

Links

Copyright ©CuriousTab. All rights reserved.