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Consider a 4 bit ripple carry adder. Each full adder is implemented using a 3 input exor gate, three 2 input AND gates and one 3 input or gate. Consider the delay of 3 input exor gate to be 3 n-sec, the delay of each 2 input AND gate to be 1 nsec and the delay of each 3 input or gate to be 1 nsec. The total time taken by the 4 bit ripple carry adder to perform successful addition operation is ________.
    Correct answer is '9'. Can you explain this answer?
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    Consider a 4 bit ripple carry adder. Each full adder is implemented us...
    The given problem asks us to determine the total time taken by a 4-bit ripple carry adder to perform a successful addition operation.

    The 4-bit ripple carry adder consists of four full adders, where each full adder is implemented using a 3-input XOR gate, three 2-input AND gates, and one 3-input OR gate.

    To calculate the total time taken by the adder, we need to consider the delays of each gate involved in the circuit.

    Given Delays:
    - 3-input XOR gate delay: 3 nsec
    - 2-input AND gate delay: 1 nsec
    - 3-input OR gate delay: 1 nsec

    Calculating the Carry Signal Delay:
    In a ripple carry adder, the carry signal is propagated from one full adder to the next. Therefore, the carry signal delay is the sum of delays from each full adder.

    - The carry signal delay for the first full adder is 0, as there is no previous carry signal.
    - For the second full adder, the carry signal delay is the delay of the XOR gate (3 nsec) plus the delay of the AND gates (3 * 1 nsec).
    - Similarly, for the third full adder, the carry signal delay is the delay of the XOR gate (3 nsec) plus the delay of the AND gates (3 * 1 nsec).
    - Finally, for the fourth full adder, the carry signal delay is the delay of the XOR gate (3 nsec) plus the delay of the AND gates (3 * 1 nsec).

    Therefore, the total carry signal delay is:
    0 + (3 + 3 * 1) + (3 + 3 * 1) + (3 + 3 * 1) = 0 + 6 + 6 + 6 = 18 nsec

    Calculating the Sum Signal Delay:
    The sum signal delay is the delay of the XOR gate (3 nsec) plus the delay of the OR gate (1 nsec).

    Therefore, the total sum signal delay is:
    3 + 1 = 4 nsec

    Calculating the Total Time:
    The total time taken by the adder is the maximum delay between the carry signal delay and the sum signal delay.

    Therefore, the total time taken by the 4-bit ripple carry adder to perform a successful addition operation is:
    max(18 nsec, 4 nsec) = 18 nsec

    However, we need to consider the carry propagation time as well. In a ripple carry adder, the carry signal has to propagate through all the full adders, which takes an additional delay.

    Since each full adder has a carry signal delay of 6 nsec, the total carry propagation time for 4 full adders is:
    4 * 6 = 24 nsec

    Therefore, the total time taken by the 4-bit ripple carry adder to perform a successful addition operation is:
    18 nsec (carry signal delay) + 4 nsec (sum signal delay) + 24 nsec (carry propagation time) = 46 nsec

    Hence, the correct answer is 46 nsec.
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    Consider a 4 bit ripple carry adder. Each full adder is implemented us...
    Concept:
    The implementation of circuit is shown
    To generate S1 [C0, A1, B1 are required]
    To generate C1 [C0, A1, B1 are required]
    To generate S2 [C1, A2, B2 are required]
    To generate C2 [C1, A2, B2 are required]
    Calculation:
    Different output and time after which they are generated are:
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    Consider a 4 bit ripple carry adder. Each full adder is implemented using a 3 input exor gate, three 2 input AND gates and one 3 input or gate. Consider the delay of 3 input exor gate to be 3 n-sec, the delay of each 2 input AND gate to be 1 nsec and the delay of each 3 input or gate to be 1 nsec. The total time taken by the 4 bit ripple carry adder to perform successful addition operation is ________.Correct answer is '9'. Can you explain this answer?
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    Consider a 4 bit ripple carry adder. Each full adder is implemented using a 3 input exor gate, three 2 input AND gates and one 3 input or gate. Consider the delay of 3 input exor gate to be 3 n-sec, the delay of each 2 input AND gate to be 1 nsec and the delay of each 3 input or gate to be 1 nsec. The total time taken by the 4 bit ripple carry adder to perform successful addition operation is ________.Correct answer is '9'. Can you explain this answer? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about Consider a 4 bit ripple carry adder. Each full adder is implemented using a 3 input exor gate, three 2 input AND gates and one 3 input or gate. Consider the delay of 3 input exor gate to be 3 n-sec, the delay of each 2 input AND gate to be 1 nsec and the delay of each 3 input or gate to be 1 nsec. The total time taken by the 4 bit ripple carry adder to perform successful addition operation is ________.Correct answer is '9'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Consider a 4 bit ripple carry adder. Each full adder is implemented using a 3 input exor gate, three 2 input AND gates and one 3 input or gate. Consider the delay of 3 input exor gate to be 3 n-sec, the delay of each 2 input AND gate to be 1 nsec and the delay of each 3 input or gate to be 1 nsec. The total time taken by the 4 bit ripple carry adder to perform successful addition operation is ________.Correct answer is '9'. Can you explain this answer?.
    Solutions for Consider a 4 bit ripple carry adder. Each full adder is implemented using a 3 input exor gate, three 2 input AND gates and one 3 input or gate. Consider the delay of 3 input exor gate to be 3 n-sec, the delay of each 2 input AND gate to be 1 nsec and the delay of each 3 input or gate to be 1 nsec. The total time taken by the 4 bit ripple carry adder to perform successful addition operation is ________.Correct answer is '9'. Can you explain this answer? in English & in Hindi are available as part of our courses for GATE. Download more important topics, notes, lectures and mock test series for GATE Exam by signing up for free.
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