Four different types of Adders are used to construct an 8-bit adder. T...
The carry generation timings are as follows:
T(C1) = 18 nsec
T(C2) = (18 + 27) nsec = 45 nsec
T(C3) = (23 + 45) nsec = 68 nsec
T(C4) = (32 + 68) nsec = 100 nsec
T(C5) = (18 + 100) nsec = 118 nsec
T(C6) = (23 + 118) nsec = 141 nsec
T(C7) = (27+141) nsec = 168 nsec
Cout = (32 + 168) nsec = 200 nsec
To find the maximum no of addition we have to find the time taken for each addition
Now, sum generation times are as follows:
T(S8) = (168 + 23) nsec = 191 nsec
T(S7) = (141 + 169) nsec = 310 nsec
T(S6) = (118 + 72) nsec = 190 nsec
We see that S7 appears at t = 310 nsec while the last carry Cout appears before at t = 200 nsec.
As, S7 takes the longest time to generate the output.
Thus, the maximum number of addition per second
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