A dynamic RAM has refresh cycle of 32 times per msec. Each refresh operation requires 100 nsec and a memory cycle requires 250 nsec. What percentage of memory’s total operating time is required for refreshes? (A) 0.64 (B) 0.96 (C) 2.00 (D) 0.32

1 Answer

Answer :

Answer: D

Explanation:

in 1ms : refresh = 32 times

Memory cycle = 1ms/250ns = 106ns/250ns = 4000 times

Therefore, % of refresh time = (32 x 100ns)/(4000 x 250ns)

= 3200ns/1000000 x 100% = 0.32%

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