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If the propagation delay through a full-adder (FA) is 150 nsec, what is the total propagation delay in nsec of an 8-bit ripple-carry adder

User Kenyee
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1 Answer

1 vote

Answer:

270 nsec

Step-by-step explanation:

Ripple-carry adder is a combination of multiple full-adders. It is relatively slow as each full-adder waits for the output of a previous full-adder for its input.

Formula to calculate the delay of a ripple-carry adder is;

= 2( n + 1 ) x D

delay in a full-adder = 150 nsec.

number of full-adders = number of ripple-carry bits = 8

= 2 ( 8 + 1 ) x 150

= 18 x 150

= 270 nsec

User Oenpelli
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