adplus-dvertising
frame-decoration

Question

A half adder is implemented with XOR and AND gates. A full adder is implemented with two half adders and one OR gate. The propagation delay of an XOR gate is twice that of an AND/OR gate. The propagation delay of an AND/OR gate is 1.2 microseconds. A 4-bit ripple-carry binary adder is implemented by using full adders. The total propagation time of this 4-bit binary adder in microseconds is

a.

19.2 microseconds

b.

18.0 microseconds

c.

12.3 microseconds

d.

16.6 microseconds

Answer: (a).19.2 microseconds

Engage with the Community - Add Your Comment

Confused About the Answer? Ask for Details Here.

Know the Explanation? Add it Here.

Q. A half adder is implemented with XOR and AND gates. A full adder is implemented with two half adders and one OR gate. The propagation delay of an XOR gate is twice that of an...

Similar Questions

Discover Related MCQs

Q. The total number of prime implicants of the function f(w, x, y, z) = Σ(0, 2, 4, 5, 6, 10) is ________.

Q. Given the function F = P′ + QR, where F is a function in three Boolean variables P, Q and R and P′ = !P, consider the following statements.

S1: F = Σ (4, 5, 6)
S2: F = Σ (0, 1, 2, 3, 7)
S3: F = Π (4, 5, 6)
S4: F = Π (0, 1, 2, 3, 7)

Which of the following is true?

Q. What is the minimum number of NAND gates required to implement a 2-input EXCLUSIVE-OR function without using any other logic gate?

Q. Using a 4-bit 2’s complement arithmetic, which of the following additions will result in an overflow? (i) 1100 + 1100 (ii) 0011 + 0111 (iii) 1111 + 0111

Q. The number (123456)8 is equivalent to

Q. The function AB’C + A’BC + ABC’ + A’B’C + AB’C’ is equivalent to

Q. Which of the following expressions is equivalent to (A⊕B)⊕C

Q. Using Booth's Algorithm for multiplication, the multiplier -57 will be recoded as

Q. How many pulses are needed to change the contents of a 8-bit up counter from 10101100 to 00100111 (rightmost bit is the LSB)?

Q. We want to design a synchronous counter that counts the sequence 0-1-0-2-0-3 and then repeats. The minimum number of J-K flip-flops required to implement this counter is

Q. Consider a carry lookahead adder for adding two n-bit integers, built using gates of fan-in at most two. The time to perform addition using this adder is

Q. Consider an eight-bit ripple-carry adder for computing the sum of A and B, where A and B are integers represented in 2’s complement form. If the decimal value of A is one, the decimal value of B that leads to the longest latency for the sum to stabilize is _____________

Q. Let X be the number of distinct 16-bit integers in 2’s complement representation. Let Y be the number of distinct 16-bit integers in sign magnitude representation. Then X −Y is _________

Q. The addition of 4-bit, two's complement, binary numbers 1101 and 0100 results in

Q. Which of the following input sequences for a cross-coupled R-S flip-flop realized with two NAND gates may lead to an oscillation ?

Q. The following bit pattern represents a floating point number in IEEE 754 single precision format 1 10000011 101000000000000000000000 The value of the number in decimal form is

Q. A processor that has carry, overflow and sign flag bits as part of its program status word (PSW) performs addition of the following two 2's complement numbers 01001101 and 11101001. After the execution of this addition operation, the status of the carry, overflow and sign flags, respectively will be:

Q. The complement of the function F = (A + B’)(C’ + D)(B’ + C) is:

Q. To put the 8085 microprocessor in the wait state

Q. Comparing the time T1 taken for a single instruction on a pipelined CPU with time T2 taken on a non­ pipelined but identical CPU, we can say that