Digital electronics miscellaneous


Digital electronics miscellaneous

Digital Electronics

  1. To add two m-bit numbers, the required number of half adder is—









  1. View Hint View Answer Discuss in Forum

    To add two m-bit numbers, the required no. of half adder is 2m–1.

    Correct Option: A

    To add two m-bit numbers, the required no. of half adder is 2m–1.


  1. In Boolean algebra if F = (A + B) ( A + C), then—









  1. View Hint View Answer Discuss in Forum

    Given, F = (A + B) ( A + C)
    or F = AA + AB + BC + AC
    or F = AB + BC + AC
    To minimize this function, it can be solved easily by using K-map given below:
    From K-map, we get F = AB + AC


    Correct Option: C

    Given, F = (A + B) ( A + C)
    or F = AA + AB + BC + AC
    or F = AB + BC + AC
    To minimize this function, it can be solved easily by using K-map given below:
    From K-map, we get F = AB + AC




  1. Consider the following logic circuit. What is the required input condition (A, B, C) to make the output X = 1?











  1. View Hint View Answer Discuss in Forum

    To get X = 1 output of EX-OR gate and EX - NOR gate must be 1 and in order to make
    Y1 = 1 → A should be 0 and B should be 1
    Y2 = 1 → C should be 1 and B should be 1. So, to
    get X = 1 the condition (0, 1, 1) is correct.


    Correct Option: D

    To get X = 1 output of EX-OR gate and EX - NOR gate must be 1 and in order to make
    Y1 = 1 → A should be 0 and B should be 1
    Y2 = 1 → C should be 1 and B should be 1. So, to
    get X = 1 the condition (0, 1, 1) is correct.



  1. What is the minimum number of NAND gates required to implement A + AB + AB C?









  1. View Hint View Answer Discuss in Forum

    Given, F = A + AB + ABC
    or F = A (1 + B) + ABC
    or F = A + ABC [since 1 + B = 1]
    or F = A (1 + BC)
    or F = A [since 1 + BC = 1)
    Therefore, minimum number of NAND gate required to implement F = A is zero.

    Correct Option: A

    Given, F = A + AB + ABC
    or F = A (1 + B) + ABC
    or F = A + ABC [since 1 + B = 1]
    or F = A (1 + BC)
    or F = A [since 1 + BC = 1)
    Therefore, minimum number of NAND gate required to implement F = A is zero.



  1. The Boolean function (x+y) ( x + y) (y+z) is equal to which one of the following expressions?









  1. View Hint View Answer Discuss in Forum

    F = (X + Y) ( X + Y) (Y + Z)
    So, F = (X + Y). ( X + Z)


    Correct Option: C

    F = (X + Y) ( X + Y) (Y + Z)
    So, F = (X + Y). ( X + Z)