For a typical design, the longest delay path through an n-bit ripple carry adder is approximately 2n + 2 gate delays. Thus, for a 16-bit ripple carry adder, the delay is

**34 gate delays**.## How many full adders are required to construct 16-bit ripple carry adder?

A 16-bit ripple carry adder is realized using

**16 identical full adders**(FA) as shown in the figure. The carry-propagation delay of each FA is 12 ns and the sum-propagation delay of each FA is 15 ns.## How many gates does a ripple adder have?

The 1 bit full adder is composed of 5 gates. The circuit is shown below. The 32 ripple carry adder uses 32 1-bit adders for a total of

**160 gates**.## How does the gate count of the 16-bit carry lookahead adder compare to that of a ripple carry adder of the same size give gate counts for both?

A 16-bit carry lookahead adder has

**82 gates**in it whereas a 16-bit ripple carry adder consists of around 80 gates.## How many outputs does a 16 bit adder have?

1 Answer. Number of inputs = 16(A) + 16(B) + 1(Cin) = 33 address bits Number of outputs = 16(sum/diff) + 1(Cout) =

**17**Thus, this would require a 2^33 x 17-bit ROM.## How many gate delays does a 16-bit carry lookahead adder have?

Carry Lookahead Adder
Thus, for a 16-bit ripple carry adder, the delay is

**34 gate delays**. This delay tends to be one of the largest in a typical com- puter design.## How do you calculate gate delay in ripple carry adder?

The gate delay can easily be calculated

**by inspection of the full adder circuit**. Each full adder requires three levels of logic.In a 32-bit [ripple carry] adder, there are 32 full adders, so the critical path (worst case) delay is 31 * 2(for carry propagation) + 3(for sum) = 65 gate delays.## Frequently Asked Questions

#### Why is n-bit binary ripple carry adder extremely slow?

Number Representation and Computer Arithmetic
Ripple-carry adders are quite simple and easily expandable to any desired width. However, they are rather slow, because

**carries may propagate across the full width of the adder**. This happens, for example, when the two 8-bit numbers 10101011 and 01010101 are added.#### What is the gate delay for a 16-bit ripple carry adder?

For a typical design, the longest delay path through an n-bit ripple carry adder is approximately 2n + 2 gate delays. Thus, for a 16-bit ripple carry adder, the delay is

**34 gate delays**. This delay tends to be one of the largest in a typical com- puter design.#### What is the gate count of 16 bit ripple carry adder?

**34 gate delays**.

## FAQ

- What is 16 bit adder?
- A 16-bit ripple carry adder is realized using
**16 identical full adders (FA)**as shown in the figure. The carry-propagation delay of each FA is 12 ns and the sum-propagation delay of each FA is 15 ns. The worst case delay (in ns) of this 16-bit adder will be. 195. - What is a 16 bit carry select adder?
- The upper adder has a carry-in of zero; the lower adder a carry-in of one. The actual carry- in from the preceding sector selects one of the two adders. If the carry-in is zero, the sum and carry-out of the upper adder are selected. If the carry-in is one, the sum and carry-out of the lower adder are selected.

## Where does the worst propgation delay occur in a 4bit ripple carry adder

What is the gate delay for a 16 bit ripple carry adder? | For a typical design, the longest delay path through an n-bit ripple carry adder is approximately 2n + 2 gate delays. Thus, for a 16-bit ripple carry adder, the delay is 34 gate delays. This delay tends to be one of the largest in a typical com- puter design. |

How many full adders are required to construct 16 bit ripple carry adder? | A 16-bit ripple carry adder is realized using 16 identical full adders (FA) as shown in the figure. The carry-propagation delay of each FA is 12 ns and the sum-propagation delay of each FA is 15 ns. |

- How does ripple carry adder work?
- Two numbers can be added by beginning with the two least significant digits to produce their sum, plus a carry-out bit (if necessary). Then the next two digits are added (together with any carry-in bit from the addition of the first two digits) to produce the next sum digit and any carry-out bit produced at this stage.

- Where does the worst propgation delay occur in a 4bit ripple carry adder
- Feb 11, 2015 — First of all you should use only full
*adders*, as stated in the problem text, your*delay will*then be one sum to*carry*plus three*carry*to*carry*.

- Feb 11, 2015 — First of all you should use only full