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ECE :: Digital Electronics

  1. The modulus of counter in the given figure is

  2. A.
    1
    B.
    2
    C.
    3
    D.
    4

  3. A 4 bit modulo 16 ripple counter uses JK flip-flops. If the propagation delay of each FF is 50 ns. The max. clock frequency that can be used is equal to

  4. A.
    20 MHz
    B.
    10 MHz
    C.
    5 MHz
    D.
    4 MHz

  5. As the number of flip flops are increased, the total propagation delay of

  6. A.
    ripple counter increases but that of synchronous counter remains the same
    B.
    both ripple and synchronous counters increase
    C.
    both ripple and synchronous counters remain the same
    D.
    ripple counter remains the same but that of synchronous counter increases

  7. In a 4 input OR gate, the total number of High outputs for the 16 input states are

  8. A.
    16
    B.
    15
    C.
    14
    D.
    13

  9. For the ring oscillator shown in the figure, the propagation delay of each inverter is 100 pico sec. What is the fundamental frequency of the oscillator output __________

  10. A.
    10 MHz
    B.
    100 MHz
    C.
    1 GHz
    D.
    2 GHz

  11. If A is 1011, A" is

  12. A.
    1011
    B.
    0100
    C.
    1100
    D.
    1010

  13. Which of the following is not a characteristic of a flip flop?

  14. A.
    It is a bistable device
    B.
    It has two outputs
    C.
    It has two outputs are complement of each other
    D.
    It has one input terminal

  15. The number of flip flops needed for a Mod 7 counter are

  16. A.
    7
    B.
    5
    C.
    3
    D.
    1

  17. For AB + A C + BC = AB + A C the dual form is

  18. A.
    (A + B) (A + C)(B + C) = (A + B)(A + C)
    B.
    (A + B ) (A + C)(B + C) = (A + B)(A + C)
    C.
    (A + B) (A + C) (B + C) = (A + B) (A + C)
    D.
    none of the above

  19. A DAC has full scale output of 5 V. If accuracy is ± 0.2% the maximum error for an output of 1 V is

  20. A.
    5 mV
    B.
    10 mV
    C.
    2 mV
    D.
    20 mV